M TF7 ii, 1W IP".5 R PON MEW RIM 4... d 6_4 4 A 14.4.............,4 A_ 4 4. N A. z 14 Aftz. P 44, V;:5................................................................................... 40 C................................................. Zi i,....................... 4u............................................................ I..................................... 14 17, 5rck........... i....................... ell........... W $,A.4. g.......... 447......................... I. r' ' k Q i, '.s. t, N 1 Y y " Y Rig F y 4. 4' J h. A t M. * t, r r,t a -,, a P A.,,Q r. A k 'Xrc' '. '., "p x, FA. Ki. M H k' a _. }. 'r r~ x, i... 1.. Al;(:,,'rc ~ "-r! t' i n ~ a h; '?.. i b.. '^ _,,, 4 y d",. f M 1 ",S [ y y.' t -"v'5r,~b rc':, 9 fq ".. a s _ _ W r a.,. *?..}.! r a 4'.". ff s ' J. of ' h u ',4." - t _ -:, p u +. T 4 f v yea, ' s.6" try,..5'-t,., a J e ry'+^ gr., kw =;' x '. " "'; ~ w. as a w e,_ L,".,fin ^. '" ~w "6 a ' '.- ' a, { ~ p~ ' ". i, yj *t' - "'. k1 '. 'mr r, r~', A+,,a.S t s K, * r r E - -!r 3 a." F 2.f,v},., + r,..4ti,,. +1 4 +..,~, '. ' r R a F, '1a x - 'e " f' n. L xs fie' 'r A;y" I.0 n 1 f Z k S /' j~,b^ 7p' ' i.ay iaN e' 'V# t uin~Y {wg ~, yV YCSt ~2 ' l" a a ' S 'i., E _' V r,,i L S 'Y a 1 ~ '.., _ y, r 'S... _.. 's -,. '; - i aka r.Y +. v s r.U r.,,,. r, S, j Div. _ yp,.. E r p}, ' ', "",' r"u'. '. 4' r' INNA v T, v'.' 14 4 a A i F. i -"M-C'y 13 i 'W. 'a * ' " ' aAt't "C " ~ < y,;y'.. r. 'w,.. K i~} " ti s..:,F;,., k 0," t " 9 i. ~ i! a r q 'Y r.. * ' - ' " ' ' - ' L ' rr '4 r a. A'N'Y tN I # '. 'd t ' Sw, ~, n r " _ ~h 6 f. e ". ' N a e' ' r ia" v ' yMn fMt v f a 4 5. elk.. 1 F. MOTIONS IN TH ATMOSPHFR' OF7 AQJILAF David. Lee A dissertation submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy, in the University of Michigan. CONTENTS Motions in the Atmosphere of Aquilae Page References i Introduction 1 Special Features of this Investigation 6 The Spectroscopic Observations 9 Measurement and Reduction 10 Wave-lengths of Selected Lines and Blends 13 Radial Velocities 14 Velocity Differences 15 Summary 21 Acknowledgement S 23 Tables 24 Plates 39 RFRENCES 1. Philosophical Transactions, 75, 129, 1785. 2. Astronomische Jahrbuch fur 1814, 144. 3. Astronorricie Jahrbuch fur 1817. 121. 4s Asbbonomisbhe Nachr ghten, 163, 362, 1903. 5. Astrophysical Journal, 44, 287, 1916. 6.Astrophysical Journal, 56, 217, 1922. 7. Astronomische Npchrichten, 183, 265, 1909. 8. Astronorlsohe Nechrichten, 225, 1, 1325. 9. Mller-iartwig, Lichtvechsel der Sterrv, 2, 229. 10. 1stroihysical Journal, 6, 393, 1897. 11 Astrophysical 'ournel, 9, 59, 1899. 12. Popular Astronomy, 32, 228, 1924; Proceedings of the Nation1 Academy of Science, 10, 264, 1924. 13. Journal of the Royal Astronomical Scciety of Canada, q 19, 82, 1?25. 14. Astrophysicl Journal, 44, 273, 1916. 15. Iroceedings of the National Academy of Science, 4, 129, 1918. 16. Popular Astronorny 32, 22, 1924. 17. Astrophysical Journal, 38, 407, 1913. 18. Astrophysical Journal, 37, 322, 1915 fnd 38, 341, 1913. 19. Publications ofAObser'vatory of the University of Michigan, 2, 112, 1916. 20. Astrophysical Journal, Table in Vofumesi and 2. 21. Astrophysical Journal, 61, 47, 1925. 22. Popular Astronomy, 32, 218, 1924. 23. Popular Astronomy, 34, 242, 1926. 0 0 MOTIONS IN THE ATMOSPHERE OF AQUILAE David W. Lee INTRODUCTION Light Variation. The discovery of the light variation of IAquilae (19h 474,.045') is usually credited to 1 2 Pigott in 1784; altho according to Wurm Justus Byrgius in 1612 noted a variable star in Antinous, which was probably the one designated 27 by Bayer and assigned different magnitudes by various observers. Bayer and Flamsteed recorded its magnitude as 3 and Piazzi marked it 5. (he visual range is from 3.7 to 4.5.) The period determined by Pigott was 7d 4 38 (7L93). Wurm3 in 1814 obtained a more accurate value of the period, 7 17604. the light period was divided by Pigott into four parts: the time of increase 3611, duration of maximum 4411, the decrease 81 and. duration of minimum 30h* Good.ricke's eclipse theory appeared to be a sufficient explanation. It was soon found, however, by Argelander and others that the law of its light variation was too complicated to be accounted for by this simple explanation and Goodricke's alternate WaS theory.favored, i.e., the rotation of a star having fixed spots that vary in size. The increase of light required about 2.7 days and the decrease 4.5 days. On the descending branch of the light curve was found a secondary maximum or pause at a phase li to 2 days after light maximum. n -2 -The period was also suspected of variability by some observers, while others rejected the idea. Luizet4 adopted a mean period of 7h76382 and a periodic term -0Ql4 sin (0.044E -304~.) Hellerich6fourd that this mean period is satisfactory, but rejected the harmonic term. Wylie6 using the photographic observations of Kohlschutter7 and his own photo-electric data finds that the value of the a period between 1906 and 1920 was 7.1?670. Changes in the form of the light curve of y 4quilae have also been suspected, especially with reference to the time and duration of the pause on the descending branch. Wylie concludes that the light curve did not change between July and November 1920. In addition to confirming the "secondary maximum" or pause in the decrease of light from phase 1.8 to 2.4 days he found another fluctuation with maximum about phase four days. Becker$ using Plassmann's data from 1895 to 1925 and combining in four year periods obtains seven curves which indicate wide variations in the form of the descending branch. Schwarzschild found in 1898 that the photographic range of variation, 1.29, is about twice the visual. Kohlschtitter's value of the photographic range is 1P09. Vtylie's photo-electric range is fh28. Changes in the value of the maxima and minima have been suspected. Radial Velocity. The variable radial velocity of > Aquilae was discovered by Blopolsky10in 1895. Assuming L - M -3 - that the period of velocity variation coincided with the thdh period oflight curve, 7d 4, and adopting the binary assumption, he computed orbital elements from twelve spectrograms obtained during July and August 1897. His results were: V: -13:.7 ]. e = 0.163 wa 901 T a 2.0 d after light minimum. a sin i 1,382,000 im. He called special attention to the fact that the "times of minimum brightness and the times for which the velocity in the line of sight is zero do not coincide. ior this reason the changes in the brightness of the star cannot be explained as the result of eclipses, and some other explanation must be sought. It is very remarkable that this is also true of the variable star 6 Cephei". He offers no other explanation of the cause of light vanat ion. Wright11 using 27 spectrograms and assuming an orbital period of 7.176 days found the following elements: V -14.16 km. E0.l7 km. e = 0.489;0.014 co:- 68Q91 11.95 2. 6 2l0;+0%288 after light maximum. K w 20.59 km. +0.36 km. a sin i: 1,545,000 km. ., y -4 -An observation at phase 3.773 days with a residual of -4.8 km. was rejected by Wright with the explanation: "It is above the limit set by various criteria for the rejection of doubtful observations, and was taken to indicate the presence during some part of the manipulation of the plate of an abnormal source of error." Atmospheric moton. In the year 1923 Doctor Rufus12 found many interesting results from the measurements of 42 spectrograms of 7/ Aquilae. The mean radial velocity curve obtained by him included a secondary variation or pause from phase 2.5 to 3.5 days which occurs about one day later than the pause of the light curve by Wylie. He also found systematic differences of line displacements at different levels, indicating a lag of phase of the higher elements especially hydrogen. Attention was called to the difference in form as well as phase of the velocity curves at e different hights. Velocity-difference curves or atmospheric compression curves were also formed and correlated with the light changes and spectral variation. In this way he accounted for the retardation of light maximum after the maximum compression of the star as a whole on the basis of the radial pulsation theory; and suggested that the pause of the light curve seems to be due to a stage of compara/3 tive rest in the atmosphere of the star. Henroteau ooiialso ed flrrwed tho wcrsk of Pfezsr Rnua by obtaining different displacements for lines of different levels in7 Aquilae. The Spectral Variation. The classification of the spectrum of?- Aquilae has been a subject of much difference of opinion, B6lopolsky placed it intermediate between Seochi' s types II and III and noted its close resemblance to the spectrum of a Oephei. Wright placed it between types I and II. In the Draper Oatalogue it is designated as class G (?). FWright found that the lines of S Oephei are better defined than those of y Auilae. ShapleyW in his study of the spectral variations of depheids found that the spectrum of Aquilae varies from A8 just before light maximum to G5 at light minimum. Using Shapley's data the spectral variation curve resembles the light curve, but the pause on the descending branch is of longer duration. Adams and Joy1( found that there is a greater range in the spectral class of the Cepheids given by the intensity of the hydrogen lines than by the general spectral features. The enhanced lines also show a greater change of intensity than the normal lines. In the case of y Aquilae enroteaul using the change in the relative intensity of a pair of lines, X4534.139 due to ionized titanium and X 4534.953 due to neutral titanium, determined a curve of the variation of ionization, which in its main features agrees quite closely with the spectral variation curve based upon Shapley's data, including a long pause on the descending branch. -64 - The change in color index determiied by Schwarzschildf' also correspondsquite closely with the spectral changevvtecit& His values are O'46 at light maximum (about F) and 1.08 at light minimum (about G5). This range is much greater than would be expected from the ganer-al spectral changeew&.cxcr SPEOTJAL FEATURES OF THIS INVESTIGATION. The Purpose of the Investigation. The purpose of this investigation is to make a systematic study of the displacements of lines of different elements originatiffny at different assumed levels in the atmosphere of71 Aquilae. In particular the effect of the systematic differences in velocities at different levels will be applied as a further test of atmospheric pulsation. A search for a possible compressional wave traveling outward from the photosphere will also be made. It is further proposed to isolate the lines due to ionized atoms and to study their difference in behavior at different levels and to compare their displacements with the displacements of lines due to neutral atoms. The relationship between these atmospheric velocity differences and the changes in light, spectral class, and the mean radial velocity of the star will be studied. It is hoped that this investigation will be a direct contribution to the general problem of Cepheid variation. The Method of Attack.16 About seventy selected lines i -m7 - of the spectrum of;j./ Aqulilae were divided into seven groups according to their height in the chromosphere of the sun as determined by Mitchell. Altho the atmosphere of 27Aquilse may be many times as extensive as the sun's. it is assumed that in general the distribution of the elements follow the same order of height in the star as in the snn, while the absolute height may be many times as great. It is well known from the work of Mitchell verified by St. Johni' that in general the elements in the atmosphere of the sun are distributed at heights according to their atomic weights, the heavier atoms occupying the lower levels. A exception to this general rule applies to the ionized atoms, which occupy higher levels than the neutral atoms of the same element. The first group of lines correspond to solar chromo spheri c heights, 300 to 550 km., the second 600 to 750, the third 800 to 900, the fourth IQO0to 1200, the fifth 1300 to 1600, the sixth 5000 to 6000 and the seventh 8000. The lack of suitable lines originating between heights 1600 to 5000 kmn. should be noted. The mean velocity curve, using lines from all levels, was formed; also individual curvce s for each of the seven groups. To study the difference in velocities at different T f In the second method the velocities obtained from the lines of the first group (the lowest) was used as the basis from which the velocity-differences were formed. Anattempt to trace the progress of a compressional wave thru the successive layers was made by deriving the velocity-differences of adjacent groups, always- subtracting the velocities of one group from the nest higher,, i. e.,2-l, 3--2, 4-w3, etc. The next step was the separation of the lines due to the ionized atoms from those due to the neutral atoms. The above method of grouping by level was followed in both divisions as far as possible and the same types of velocitydifference curves were formed. Differences were then formed between the velocities of these two classes of lines for each level, and between the mean of all lines due to the ionized atoms and the mean of all lines due to the neutral atoms. 4.. THE SPECTROSCOPIC OBSERVATIONS Table of Observations. Table I contains a list of 71 the observations. Oolumn one gives the plate numbers; column two the time of mid-exposure expressed in Greenwich mean time; column three the duration of exposure; column four the phase after light maximum; column five the observer designated 0, R, Ro, M4 D and. L, respectively for Curtiss, Rufus, Rossiter, McLaughlin, Dustheimer and Lee; column six contains some remarks. The Spectrograms. The spectrograms used in this investigation were made with the spectrograph attached to the 37 inch Cassegrain reflecting telescope of the Observatory of the University of Michigan. Seed 23 photographic plates were used. The quality of the spectrograms is uniformly good, as all poor plates, those with unequal comparison or weak stellar spectrum were rejected. This was done in an attempt to measure every line used in the investigation in each one of the plates and. to retain every measurement and resulting velocity. The Quality of the Lines. As pointed out by Wright; "The lines which are fairly numerous, have the general characteristics of breadth and haziness, which tend to make them objectionable for purposes of accurate measurement.' . " i 4 r " r -ld" These characteristics also complicate the difficulties introduced by the blending of close lines which would be tesolved if they were sharper and more clearly defined. Another obstacle is the unequal change of intensity of the components of blended lines due to the periodic change of spectrum, which produces a greater effect on the enhanced lines than on the normal lines. It was found that this difficulty was greater on plates that were weak, and consequently several spectrograms were rejected that would otherwise have been considered suitable for radial velocity determination. MEASUE ENT AND REDUCTION Measurement. The spectrograms were measured on measuring engine number five of this observatory, which is provided with a photographic reticle having an interrupted line to take the place of the ordinary cross-hair. Three settings were made on each line measured; then the plate was reversed and the process was repeated to reduce the / personal equation as much as possible. About twenty titanium spark lines were measured on each plate for the comparison spectrum. The Standard Table. The standard table containing twenty-five star lines, which had been prepared by Professor Rufus for his preliminary work on q Aquilae, was extended by the following method. Three good plates, one at light at Nita. maximum, one at light minimum and one at the light pause, Were selected and all the lines were measured.. From this survey about 50 additional lines were selected., special attention being given to include as many of Mitchell's high level lines as possible. Ten of the best plates, well distributed in phase, were then selected., and seventyfive lines including the twenty-five previously used were measured. The mean of the micrometer readings for each of the 75 lines on the ten plates was determined. The radial velocities were( a o- found by using the twenty-five standard lines and the mean from all lines of the ten plates was computed. With this value of V the mean displacement R for each one of the 25 standard lines was found by using values of SEM d from the standard table. By dl? means of interpolation, the values of AR for the 50 new lines were determined.. These corrections were applied to the mean of the micrometer readings to obtain the value of It for the new lines of the standard table to which all the subseqyent measurements were referred. Later a few t lines were rejected and others substityed leaving a total of 68 lines. Table II contains the adopted standards for the lines r " r -12 - Preliminary Wave-len the. Sufficient consideration was then given to wave-lengths for the purpose of verifying the identification of lines. Using the values of R as previously determined the wave-lengths were computed by means of the Eartmann formula X.2 2197.6882 227282866 186.184 - R The computed values were corrected by applying the ordinates of the correction curve corresponding to the micrometer readings. Comparison with the Rowland wavelengths as given by Mitchell showed fair agreement at this stage of the work; altho further consideration was deemed advisable after all the measurements should be made. Radial Velocit Determination. The method of velocity determination proposed by Professor Curtiss and taught in this Observatory was followed. It was necessary, however, from the natire of the problem to keep the velocities for the individual lines separate. 71 plates were measured and reduced. Phases were determined from the formula adopted by Wright: Maximum = J.D. 2,422,606.652 - 7%176382. The rese~cctcc suits were tabulated for each line on the 71 plates. In A order to reduce the lines to approximate homogeneity, the mean velocity for each line from the total number of plates was found. The mean of these means was taken and corrections for each individual line were applied to reduce the velocities to the same zero. Alij Y -n13-s The Data Sheet. The results from the 71 plates were then combined into 24 places for each line by grouping three places into one arbitrarily according to phase, the last place having only two. These reduced data, upon which all the further work is based, are given ine Table III. WAVE-LENGTHS OF SELECTED LINES AND BLENDS The Corrections. The velocity corrections, which were determined and applied to render the lines homogeneous, provided data sufficient to correct the provisional wave-lengths computed for the purpose of identification. Multiplying the velocity correction A v by the factor ~ 71 for the corresponding wave-lengths gave the corrections to be applied to the computed wave-lengths. The Identifications. The width of each line was measured in terms of R and the corresponding value in terms of?. was used to indicate the range of spectrum included in the measured line or blend. All the chief lines given i Rowland' s Preliminary Table of Solar Spectrum Wave-lengths20 within the limits thus found for each blend were then c omb ine d by weighting them according to their intensities; and the resulting wave-lengths together with the values determined in the star are given inTable IV. Rowland'is -'i RADIAL VELOCITIES The Displacements. On the assumption that the line displacements are due to the Doppler effect radial velocities were determined for all the measured lines. Systematic differences in displacements for different elements at different levels found by Professor Rufus and confirmed by Doctor Henroteau have been corroborated and a more detailed analysis has been carried out. The Mean Radial Velocity Curve. (Plate 1). Combining the radial velocities from the lines of all levels a mean radial velocity curve was formed. The chief feature is a hump or pause on the ascending branch between phases about 2.5 days and 3.5 days after light maximum. This occurs near the "center-of-mass" velocity, or on the assumption of radial pulsation of the star as a whole it is vo lzucme at the time of the greatest ennaoni. Orbital elements were not determined, so the following data are entirely empirical. The minimum velocity -22.2 km. occurs at phase about 0.4 days; the maximum 11.3 km, at 5.6 days; giving an amplitude of.33.5 km., which is nearly 8 km. smaller than found by Wright. Minimum and maximum velocities follow maximum and minimum light by an interval of about one-half day. The ascending branch of the curve occupies 4.8 days and the descent 2.4 days. The center-of-mass velocity is about -7 kin., which differs from the one found by Wright -14 km. The difference may indicate a variation in the center-of-omass velocity, as in the case of S Sagittae; although the difference in the method used renders this conclusion uncertain. Velocities at Seven Arb itrary Levels. (Plate I). In general the maxima are quite broad and flat with an indication of becoming sharper at higher levels. No systematic difference in amplitude is indicated. A progressive lag of phase of the higher levels appears to be well established. At maximum velocity and minimum velocity its value is about 0.3 day. The pause is also later at higher levels, although the regular progression is not clearly indicated. In particular the sixth level appears to be discrepant, as the pause begins as early as in the first level. This may be due, at least in part, to its poor determination, as this group contains only four lines; or it may be attributed to an ionization effect which will be discussed later. The beginning of the pause for tbe lowest level is about phase 1.9 days and the end 2.9 days. In general the dura Levels.. (Plate 2). The mean radial velocities using the r 7 " f lines of all levels was used as a standard from which the deviations of the different levels were measured. The physical significance of the mean velocities is evidently the average rate of rise and fall of the atmosphere as a whole; so the velocity differences found by taking the mean velocity from the velocities of the different levels should reveal the behavior peculiar to each level. These results are evidently dependent on the effective height of the mean of all levels. The vel ocity-di fferences two-minus--mean form approximately a straight line suggesting that the second level closely corresponds in its motion to the mean of all levels. This level corresponds to a height of 600 km. to 750 km. in the atmosphere of the sun. There appears to be evidence of an increase of amplitude of the velocity-difference curve s with height, part of which may be a phase effect. Some of the levels, however, give deviations which are opposite in sense to the general order. These apparent inconsistencie s are partly explained by the separation of the level groups into two sets of lines, one due to neutral atoms and the other to ionized atoms. Deviations from the Lowest Level.. The velocity differ-m -17 - the errors in the velocities of the first group enter into all the results. An attempt was made to obtain a smoother curve for the first level by weighting the observations using their residuals from the arithmetic mean and the quality of the lines on the spectrograms. The result was not entirely satisfactory and it seems quite probable that the grouping of lines due to neutral atoms with those due to ionized atoms caused part of the difficulty. The same trouble was encountered in the attempt to form the veloc-. ity differences of one level from the next in order of height. The close resemblance of the velocity-difference carves, two--minus--one and hydrogen-minus-one, with the amplitude of the second about twice that of the first, is evidently due to the fact that the results are based chiefly on lines of the same nature with the added phase effect at the higher level. Velocity Differences from Ileutral Atoms.& 28 lines due to neutral atoms are distributed in the level groups as follows:; 9 in the first, 8 in the second, 6 in the third, 1 in the fourth, 1 in the sixth and ai4 3 in the seventh. It is clearly evident that reliable results can not be obtained for the intermediate and higher levels the lower levels. Two-minus--mean shows very small amplitude." One--minus--mean and three -minus--mean give similar results with long flat maxima at phase 4 to 5 days and sharper minima just before 7 days. The three velocity-difference curves from neutral atoms for levels two-minus--one, three-minus-two and fourminus-three are interesting. They are plotted in plate 3 with broken lines to conned t the observations in order that the resemblance of some of the secondary features may be compared. Although the range is not large C5 to 10 kin.) the systematic distribution and the greater accuracy of the differential method lend support to the reality of the results. Special attention is called to the regular progression of several similar features. A maximum and minimum occur in the first curve at phases - and2& days respectively. The samne features are evident about one day later in the second curve and about two days later in the third with an irregular maximum and a somewhat greater lag of the minimum. A lag of about one day be,tween the first and second curves is also indicated by a secondary minimum which occurs in the first at phase r n 4 i A f A'--- light maximum in the lowest curve appears like a compressional wave followed by the minimum which indicates expansion. This compression in the lower atmosphere may be due to an upward acceleration at the time, the star begins to expand. If the phenomenon is real the progress of the compressional wave may be traced as far as the fourth level. The synchronous features in curves two and three occur after the star has reached the greatest radial expansion, the prominent maxima at &j days indicating that the lower levels (two and three) are falling more rapidly respectively than the next higher levels (three and four), This takes place after the original upward impulse has spent its force and the gases are freely falling. Velocity Differences from Ionized Atoms. The 2 selotion of lines to represent the systematic motion of A the ionized atoms gave some difficulty on account of the numerous blends compose4 of both neutral and ionized components. Selections were made of lines due to ionized atoms alone or in which the very weak neutral components are negligible. To these were added several good blends in which the ionized component is much stronger than the neutral. Twenty of the beet representative lines were selected in this manner. The mean velocities from the n - A 0 twenty lines were found, also the velocities for the different levels. The differences from the mean were formed for each level. The chief features seemed to be approximately synchronous. The differences from the first level (Plate 4) confirmed the above result and brought out an interesting comparison with the velocity-differences of the neutral lines, viz., the continuance of the special features during ascent and the gradual dying out during fall when gr avitation becomes predorinent. The result of the strong impetus just preceding light maximum is also clearly demonstrated. Velocityr Differences, Ionized minus Neutral. (P~tg. 5). Three curves were formed at levels ohe, two and three, where data were available for comparing the motion of the ionized and the neutral atoms. The three curves are qui4te similar in form with prominent maxima about J day before light miniw mum and minima about the same length of time before light maximum. A fourth curve was formed by taking the differences between the velocities obtained from all the enhanced lines and the velocities from all the normal lines in the same sense ionized minus neutral. The principal maximum and minimum agree with the corresponding features in the separate f 1 I to the radial velocity curves can not fail to attract attention. The chief features, however, of this velocity-difference curve ionized-minus-neutral precede the corresponding ones of the mean velocity curve by about one day. The positive differences, ionized minus neutral, indicate an excess of of fallthe ionized atoms with reference to the neutral with a maximum at 4 days and the negative differences indicate an excess of rise with a maximum at 6 days. These phases agree fairly well with the minimum and maximum of ionization as found by Henroteau, although the maximum of his curve is drawn a little later. Ti-ae results are in SCGGACLXe wjtb sinilar onee found in? Geminorum by Professor Rufus. SUMARY 1. The secondary variation on the ascending branch mean of the radial velocity curve of 7 Aquilae has been confirmed. 2. A change in the velocity of the center of mass is suspected. 3. Systematic differences in line displacements at seven different levels in the atmosphere of this star have been measured. 4. A gradual increase in the general lag of phase of the radial velocities at higher levels has been established. V - a 5. Special features of the velocity-differences of the neutral atoms suggest a compressional wave which was traced through four of the lower layers of the atmosphere. 6. The predominating effect of an upward impulse has been noted during the period of ascent. 7. An ionization effect on line displacements has been isolated and correlated with the light and velocity phases and with Henroteau's variation of ionization. 8. Assuming that these displacements are Doppler effects a circulation of the ionized atoms has been observed with a maximum fall preceding light minimum about one half day and maximum rise preceding light maximum by the same length of time. 9. Support is evidently found for the radial pulsation theory of Cepheid variation supplemented by atmospheric pulsation. -A 3 " The writer desires to express his grateful appreciation of the privileges extended by Director iussey for the use of instruments and materials and for his cont inued interest during the progress of this work. Special acknowledgement is made of the assistance given by Profess or Rufus, whose preliminary work on Aquilse was made available, and under whose direct supervision the results of this investigation were rendered possible.s Thanks are also extended to Professor Curtiss and other members of the Observatory staff for cooperation in securing the spectrograms upon which this study was based. TABLE I, Date: G.M.T. Duration of Exposure Phase Obser- Notes ver 1923 6199 May 24.786 0h 50m 6215 May 29.775 0 40 6216 May 29.809 0 38 6228 June 4.872 0 30 6240 June 15.816 0 40 6254 June 26.699 1 0 6260 June 28.668 0 50 6265 June 29.797 0 24 6272 June 30.819 0 36 6275 July 2.736 9 32 6280 July 3.683 0 25 6281 July 3.706 0 20 6282 July 3.720 0 20 6283 July 3.740 0 22 6284 July 3.764 0 26 68287 July 7.705 0 44 6296 July 12.775 0 24 6306 July 16.649 0 25 6307 July 16.668 0 30 6312 July 17.672 0 22 6313 July 17.694 0 11 3.682 1.495 1.523 0.408 5.175 0.707 2.675 3.805 4.827 6.745 0.514 0.536 0.557 0.571 0.595 4.536 2.423 6.304 6.323 0.150 0.172 R R R Ro Ro R R Ro Ro Ro R R R R R Ro Ro R I I R New Prism Dustheimer assisting Iustheimer assisting Dustheimer assisting r,,. r M r a TABL3 I continued Date:, G.M.T. Duration of Exposure Phase Obser- Notes ver 6348 635]. 6352 6384 6392 6393 6406 6421 6422 6565 6578 6804 6805 6811 6837 6847 6848 6858 6859 1923 July 18.802 July 25.764 July 29.727 Aug. 13.796 Aug. 14.700 Aug. 14.728 Aug. 22.815 Aug. 23.684 Aug. 23.715 Aug. 25.693 Aug. 28.595 Aug. 28.623 Oct. 25.609 Nov. 1.612 1924 Apr. 26.817 Apr. 26.480 Apr. 30.892 May 15.809 May 20.793 May 20.816 May 22.721 May 22.757 0h 11m 0 30 0 33 0 27 0 22 0 24 0 20 o 30 0 28 0 36 0 34 0 36 0 20 0 45 0 40 0 48 0 48 0 40 0 36 0 30 0 45 0 40 1.280 1.066 5.029 5.745 6.649 6.677 0.418 1.280 1.312 3.290 6.190 61.220 6.794 6.621 4.416 4.439 1.315 1.879 6.863 6.886 1.615 1.651 0 C D Ro R R M R R M R R R R B R M R R R R R Left spark failed. a r, e TABLE I continued. Date: G.M.T. Duration of Sxpo sure Phase Obser Notes ver 6886 6913 6914 6921 6933 6937 6941 6945 6953 6963 6987 6989 7007 7014 7021 7047 7074 7093 7132 71,71 1924 June 4.824 0h June 9.860 0 June 30.681 0 June 30.715 0 July 1.835 0 July 3.631 0 July 3.766 0 July 4.808 0 July 5.694 0 July 10.682 0 July 12.686 0 July 20.684 0 July 22.658 1 July 26.808 0 July 31.810 0 Aug. 2.627 1 Aug. 14.615 0 Aug. 17.665 0 Aug. 21.699 0 Aug. 24.703 0 Aug. 28.648 0 Sept, 2.657 1 Sept 18.627 1 Sept 22.696 0 40m 48 50 50 40 40 30 40 40 34 40 55 0 56 45 0 30 30 32 35 36 0 0 30 0.365 5.401 4.692 4.727 5.847 0.466 0.601 1.643 2.530 0.341 2.345 3.167 5.140 3.114 7.117 1.757 6.568 2,442 6.476 2.304 6.249 4.081 5.*699 2.591 M M Li R R Ro R Ro Ro Ro It to D R Ro R Ro R M L M L It Schiefer assisting. Sohiefer assisting. Dustheimer assisting. Cut off by clouds. Lee assisting. Cloude part of the time. Schiefer assisting. Light haze at beginning. Haze during exposure. aw -27y TABLE I continued Plate Date: G.M.T. Duration Phase Obser- Notes Nium- of ver her Exposure 1924 7g53 Sept. 25.540 Oh 40m 3.435 R 7254 Sept. 23.567 0 38 3.465 R 7270 Sept. 25.624 1 0 5.519 L 7382 Oct. 22.582 0 48 3.772 C Y i A TABLE 2. THE STANDARD TABLE Star Lines 4005.24 4012.51 4024.94 4045.89 4063.82 4067.06 4071.71 4077.89 4101.92 4118.59 4127.67 4132.42 4154.41 4156.52 4161.45 4163.74 4187.51 4191.70 4198.64 4205.15 4215.58 4226.96 4233.58 4236.19 4242.76 4247.07 4250.76 4254.57 4258.52 4260.74 4271.85 4275.01 4282.83 4289.77 4294.32 4299.96 4305.89 4314.87 4321.11 4325.74 R 60.441 60.944 61.796 63.206 64.388 64.599 64.901 65.299 66.825 67.862 68.419 68.708 70.029 70.154 70.445 70.530 71.960 72.200 72.595 72.963 73,548 74.179 74. 542 74.686 75.044 75.278 75.474 75,632 75.894 76.013 76.603 76.770 77.180 77.542 77.778 78.069 78.373 78.831 79.147 79.380 dv /d R 1.08 1.08 1.09 1.11 1.13 1.13 1o14 1.15 1.17 1.19 1.19 1200 1.22 1.22 1.23 1.23 1.25 1.25 1.26 1.27 1.28 1,29 1.30 1.30 1.30 l"31 1.31 1.31 1.31 1.31 1.32 1.33 1.34 1.35 1.35 1.36 1.87 1*37 1.38 1.38 4330.77 4337.83 4340.53 4344.43 4351.76 4368.73 4374.84 4383.66 4395.36 4400.73 4405.03 4408.24 4415.17 4435.33 4443.81 4455.06 4461.78 4468.96 4501.44 4533.91 4549.74 4553.94 4563,~68 4571.93 4583.55 4824.06 4855.55 4861.54 R 790.632 79.984 80.118 80.311 80.672 81,498 81.792 82.214 82.768 83.021 83.222 83.372 83.694 84.619 85.003 85.508 85.807 86.125 87.537 88,909 89.564 89~736 90.133 90.467 90.933 99.651 100.675 100.8367 dv/dR 1.39 1.40 1.40 1.40 1.41 1.43 1.43 1.44 1.45 1.46 1.46 1.46 1.47 1.48 1.49 1.50 1.51 1.52 1.56 1.59 1.61 1.61 1.62 1.64 1.66 1.89 1.92 1.93 G., d a r.. < < p 4., a i a t 1 p 4 y 0 a ' r. i L D * i TAB3LE 2 Continued Comparison ftines 398.'.93G3 4009.131 4028.4::5 4078#.659 4163.838l 4172 a0283 4263. a38~ 43060078 4383.123 4399.332 '444.*049 4408 *70)9 4518.277 4563. 941 4682.07-- 47 58.917 4805"333 4:,,'85.o255 4931. 933 R, 59.305 60.711 62.037 65. 349 70.535 71.007 76.,o153 78.33 79.9 9 82. 984 85.011 86.110 88.2 50 90o144, 94.710 97.454 99.037 101.619 104. 550 r a r, ti b 4 -3o-0 TABLE III DATA SHEET Chromospheric Heights 300 km. to 550 km. Phase1 4067.06 2 4127.67 3 4132.42 4 4154.41 5 4156.52 6 7 8 9 10 11 12 13 14 4191.70 4205.15 4258.52 4368.73 4374.84 4415.17 4455.06 4461.78 4855.55,1 0.221 -23.1 -16.4 -22.7 -24.6 -20.0 -24.2 -25.2 -25.8 -27.4 -22.8 -23,6 -26.3 -25.0 -19.4 -22.4 -19.3 -22.1 -20.4 -19.9 -23.8 -22,4 -23.6 -26.4 -19.2 -19.8 -22.7 -20.1 -19.0 - 9.0 -17.3 -16.5 -20.9 -16.9 -22.3 -21.7 -23.4 -21.7 -24.5 -19.5 -24.0 -26.0 -22.4 2 3 4 0.397 0.505 0.574 -13.5 -15.5 -20.3 -17.7 -16.0 -14,0 -21.3 -22.7 -17.1 -18.9 -19.1 -25.0 -22.3 -16.7 5 0,791 -20.5 -14.1 -18.8 -23.4 -24.1 -21.9 -22.9 -25.9 -27.2 -19.0 -24.0 -25.2 -25.2 -16.6 6 1.291 -10.8 -11. 2 -11,9 -17.4 -17.3 -12.4 -12.6 -20.8 -16.1 -17.0 -17.6 -17.6 -20.7 -22,7 600 to 750 km. 1 4084.94 2 4118.59 3 4161.45 4 4163.74 5 4187.51 6 4198.64 7 4236,19 8 4242.76 9 4250.76 10 4254.57 11 4260.74 12 4282.83 13 4305.89 14 4330.77 15 4344.43 16 4351.76 17 4435.33 18 4824.02 -24.2 -19 7 -24.5 -23.5 -26.5 -24.4 -23.2 -24.1 -20.2 -27.6 -24.9 -18.7 -21.1 -26.6 -14.6 -21.3 -23.3 -24.4 -19.8 -22.3 -20.7 -22.2 -20.1 -21.1 -21.2 -24.5 -19.9 -20.5 -22.4 -21.2 -20.6 -22.4 -19.5 -20.0 -20.3 -16.7 -15.2 -21.7 -16.8 -22.7 -25.2 -25.0 -20.5 -26.8 -16.6 -14.7 -24.8 -24.6 -22.2 -26.8 -15.8 -19.7 -22.0 -20.9 -15.3 -18.5 -15.9 -15.3 -17.0 -21.6 -20.2 -25 *.9 -20.6 -20.8 -21.5 -24.6 -20.4 -19.9 -18.2 -18.4 -20.2 -21.5 -21.3 -20.7 -20.5 -24.8 -25.0 -22.5 -21.8 -25.7 -22.8 -21.8 -24.7 -22.2 -26.4 -24.7 -24.2 -21.9 -18.5 -21.5 -16.2 -16.5 -17.5 -13.6 -17.4 -16.3 -17.5 -18.8 -14.9 -10.8 -19.1 -18.8 -17.1 -17.1 -18.1 -20.9 -19.3 -15.8 TABLE III continued. 800 to 900 km. 1 4005.24 2 4012.51 o 3 4963.82 4 4071.71 5 4271.85 6 4275.01 7 4314.87 8 4321.11 9 4325.74 10 4337.83 --23.1 -24.8 -23.6 -17.3 -29.8 -25.4 -26.0 -26.2 -26.3 -23.6 -18.4 -19.9 -21.1 -18.8 -18.8 -19.6 -17.6 -16.2 -20.3 -24.0 -15.0 -25.0 -21.7 -20.4 -22,4 -22.1 -23.4 -23.2 -23.3 -19.7 -14.3 -18.8 -19,5 -15.8 -18.3 -20.0 -25.3 -17.3 -19.6 -21.6 -24.3 -19.8 -21.7 -20.9 -21.1 -21.1 -26.1 -22.1 -24.6 -26.4 -25.7 -20.3 -15.9 -19.8 -16.5 -17.6 -16.8 -15.9 -20.9 -19.9 -15.1 -15.3 11 4400.73 12 4405.03 -20.9 -24.6 -20.0 -17.5 -20.6 -21.4 -24.5 -16.2 -21.8 -19.9 1000 km. to 1200 km. 1 2 3 4 5 6 7 4045.89 4233.56 4294.32 4299.96 4533.91 4571.93 4583.55 -23.9 -24.1 -26.7 -26.9 -19.1 -19.9 -14.3 -24.2 -20.6 -21.9 -17.1 -17.5 -23.8 -23.5 -17.7 -19.0 -15.9 -23.5 -18.5 -14.9 -24.0 -24.7 -23.7 -18.7 -14.5 -16.7 -16.5 -17.6 -16.4 -19.1 -17.2 -19.3 -22.3 -17.2 -20.1 -21.7 -22.0 -18.1 -16.0 -13.7 -17.8 -18.2 1300 km. to 1600 km. I 2 3 4 5 4289.77 4443.81 4468.96 4501.44 4549.74 -20.7 -20.2 -18.0 -23.8 -15.3 -21.0 -20.2 -22,6 -22.8 -18.6 -20.3 -25.7 -25.9 -22.7 -24.2 -18.1 -18.9 -21.8 -22.2 -17.3 -24.2 -20.0 -21.3 -26,7 -21.3 -17.7 -18.2 -16.6 -18.0 -19.8 5000 km. to 6000 kmn. 1 2 3 4 4077.89 4215.58 4226.96 4247.07 -24.0 -24.5 -24.5 -24.0 -22.2 -22.2 -20.0 -21.6 -24.8 -23.6 -22.6 -22.4 -19.3 -23.2 -21.3 -22.1 -16.8 -28.9 -20.8 -23.4 -15.3 -18.5 -19.7 -21.4 8000 km. 1 2 3 4101.91 4340.53 4861.54 -24.2 -20.0 -24,0 -21.3 -14.8 -23.1 -16.3 -17.3 -17.6 -20.5 -21.9 -21.3 -22.7 -19.1 -21.2 -14.9 -18.1 -18.9 -32-- TABLE III DATA SHEET Chromospheric Heights 300 km. to 550 km. 7 8 9 10 11 1.444 1.636 1.917 2.209 2.403 12 13 2.588 3.297 14 15 3.639 4.101 I 2 3 4 5 6 7 8 9 10 11 12 13 14 -10.7 -10.1 -16.2 -18.3 -16.1 -17.8 -19.5 -11,0 -11.2 -11.7 -13,5 -15.6 -17.0 -17.7 -14.8 -11.4 -14.7 -12.3 -15.9 -11.3 -12.1 -14.6 - 8.9 -15.5 -15.8 -15.4 -14.2 -19.9 -13.8 -12.5 -13.2 -13,7 -15.9 -11.5 -13.2 -11.8 -14.3 - 7.6 - 9,5 - 0.9 - 9.1 -4.9 -16.1 -14.6 -17.7 -19.0 -15.2 -16.2 -16,2 -10. 6 -8.7 -10.1 -12.6.- 2.6 - 5.2 -1.2 -10.3 -103 3 -13.1 -13.0 - 8.9 -14.1 -19.7 -17.7 - 7.8 - 9.4 - 9.8 -12.7 -10.4 -14.6 0.4 -14.8 -12.0 - 5.9 0.0 - 9.3 - 6.8 - 6.7 - 4.8 -10,3 -7.9 - 3.8 - 0.9 - 8.5 -14.9 - 9.5 - 3.3 - 8.2 -1.8 - 4.5 - 3.4 - 4.7 - 5.9 - 2.4 - 4.6 -10.2 - 4.5 - 2.5 -11.3 - 8.4 - 1.2 - 6.2 - 6.3 - 6.6 - 6.4 - 6.5 0.8 - 2.2 - 5.2 - 9.7 -4.3 - 0.2 -12.6 sm..... w ow 5.9 1.8 2.1 2.0 4.7 - 0.2 2.1 3.5 - 2.3 - 5.1 - 2.3 - 2.3 1.0 - 7.2 600 to 750 km. I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 -14.9 - 9.2 -14.6 -12.3 -17.0 -16.0 -17.1 -15.0 -11.3 -10.8 -10.4 -11.9 -20.0 -11.5 -14.5 -11.4 -12.9 -15.0 -19.3 -12.0 -11.6 -11.3 -16.8 -14.4 -10.0 -12,2 -15.4 -16.7 -22.3 -14.2 -13.0 -21.7 -13.2 -12.0 -16.3 -16.7 -15.0 -17.3 -14.1 -15.6 -11.6 -10.4 -10.9 -11.5 -13.5 - 8.4 - 9.2 - 9.9 - 4.7 - 5.7 -15.0 -12.6 - 9.0 -13.9 -17.7 -12.5 -17.5 -17.1 -13.9 -14.0 -13.3 -12.0 -18.0 -18.9 -14.1 - 5.2 -10.8 - 9.5 - 2.6 - 8.4 -12.2 -11.5 -11.3 - 7.2 -11.0 -10.5 -13.8 -11.3 -16.4 -14.5 - 9.5 -10.8 - 7.6 -15,1 -10.4 -16.1 - 3.7 - 8.5 - 3.1 - 9.9 -11.8 - 1.4 - 9.8 -11.1 - 6.5 - 8.6 -15.5 - 4.2 - 5.4 - 4.0 - 3.9 - 9.0 - 9.3 - 6.9 - 5.9 - 5.7 - 9.7 -11.2 -10.8 - 0.7 - 9.3 -,10.9 - 4.1 - 7.7 - 9.2 - 9.4 -17.3 -11.3 -9.0 - 5.1 - 4.5 - 6.5 2.5 - 5.0 4.2 - 5.2 - 8.5 -11.5 - 3.1 - 5.5 - 6.2 - 8.5 - 3.0 -15.4 - 0.4 1.0 4.8 - 5.3 - 2.4 3.6 - 6.0 -11.5 - 5.3 - 2.9 5.3 - 1.4 - 4.8 16 -19,9 17 -12.0 18 -15.5 -14.2 -11.6 - 8.0 - 1.0 -6.7 - 7.4 - 2.7 - 5.1 -13.8 - 6.2 - 3.3 0.2 TABLE III continued 800 to 900 km. 1 2 3 4 5 6 7 8 9 10 -12.2 -13.6 -19.4 -17.6 -13.5 -17.8 -13.1 -13.8 -13.9 -11.8 -11.4 -11.0 -13.8 -16.5 -18,4 -10.8 -13.8 -15.9 -18.4 -11.9 -15.0 -10.2 -18.4 -13.8 -11.0 - 6.7 -5.7 - 4.5 -12.4 - 8.2 -10.3 - 9.8 -24.6 -16.3 -16.0 -11.0 -11.5 -10.1 -14.8 -12.7 - 9.4 -12.1 - 8.6 -13.3 -13.1 -12.5 - 9.6 - 6.5 -18.5 - 5.8 - 5.0 - 4.5 -14.4 - 2.3 - 6.5 - 4.5 - 2.8 - 6.5 - 6.6 - 8.9 -13.0 - 9.0 0.1 - 2.2 - 3.8 - 3.3 -6.4 - 7.5 - 5.7 - 9.4 - 7.7 - 2.2 0.5 - 2,7 - 0.3 - 5.1 - 2.4 - 4.1 - 1.1 - 3.8 go dw - - - mm 9.3 3.4 0.4 0.9 1.7 2.0 1,5 - 3.1 4.1 -3.9 8.2 - 2.8 11 -17.3 12 -18.0 -14,3 - 7.8 - 8.8 - 6.3 - 6.3 -17.6 - 3.8 - 8.2 - 4,5 - 8.8 - 3.7 - 4.7 - 9.7 - 9.4 1000 kml. to 1200 km. 1 2 3 4 5 6 7 -17.4 -19.9 - 9.6 -16.7 -13.5 -12.1 -13.9 - 9.8 -16.5 -10.9 -13.0 -16.9 - 8.0 -17.8 -13.9 -14.9 -12.4 - 8.2 -10.3 -13.4 - 9.6 - 8.3 -22.6 - 7,1 - 0.2 -12.0 - 8.9 - 9,9 - 7.6 -13.2 -10.1 - 8.5 - 9.3 - 8.7 -13.6 - 6.1 - 9.3 - 4.4 - 4.3 -11.8 4.0 - 7.8 - 0.2 0.4 3.8 - 9.2 1.7 -16.6 -18.5 -11.0 - 6.3 - 5.4 - 9.7 -13.7 -17.3 -12.1 - 9.9 -13.1 - 8.6 - 8.8 -14.4 - 3.3 - 3.0 1300 km. to 1600 km. 1 2 3 4 5 -18.0 -18.3 -20.2 -17.7 -17.3 -13.0 -19.2 -14.7 -19.8 - 8.7 - 6.6 -10.7 - 7.3 - 6.6 - 4.6 -12.3 - 9.3 - 6.1 -11.9 - 6.2 - 8.2 -15.0 -15.1 - 9.9 - 9.5 - 7.9 - 9.2 - 6.2 - 9.1 - 9.9 - 7.7 -7.1 - 6.8 - 9.8 -12.4 -10.2 -11.9 - 0.6 - 1.4 - 8.1 -11.1 - 2.5 1.1 - 4.4 - 5.6 5000 km. to 6000 km. I 2 3 4 -15.1 -14.5 -14.3 -12.0 -15.8 -13.0 -15.7 - 8.6 -16.4 -17.0 -13.5 - 8.8 -14.3 -16.9 -13.9 - 7.7 -10. 5 -11.8 -12.4 - 8.4 -10.8 -12.1 - 8.4 -10.2 - 7.2 - 5.3 - 8.1 - 5.2 - 5.0 - 2.4 - 2.7 - 2.4 - 6.5 - 0.4 4.9 - 2.3 1 2 3 -13.0 -16.1 -1.22 -14.1 -13.7 -14.7 -16.4 - 8.1 -14.6 8000 km. -14.1 -12.2 -17.3 -10.3 -11.6 - 8.7 - 8.6 - 8.1 - 7.9 -10.6 - 6.6 - 8.2 - 3.8 - 9.4 -4.9 - 6.6 - 1.0 - 9.2 -39 TABLE III DATA SHEET Chromospheric Heights 300 km. to 550 km. 16 17 18 19 20 21 22 23 24 4.556 4.861 5.278 5.764 6.220 6.368 6.631 6.801 7.007 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1.7 4.9 9.5 7.0 6.3 16.8 4.3 11.7 2.3 4.7 4.7 8.5 - 2.9 3.1 2.4 10.9 7.6 7.7 2.8 11.5 16.2 12.1 10.3 3.7 4.8 21.8 6.3 8.8 10.9 11.6 9.1 8.5 6.8 14.0 10.0 7.9 12.3 10.4 15.8 16.9 18.3 13.6 9.8 14.1 15.1 10.8 9.6 15,.1 9,2 7.6 6.9 12.1 10.2 13.3 8.1 10.6 8.4 4.0 9.0 8.3 16.9 12.2 1.1 6.6 10,4 3,5 1.0 5.5 6.8 - 4.5 6.6 - 0.4 1,5 2.1 0.6 - 0.8 - 4.1 - 7.9 - 7.8 3.0 - 5.3 6.8 - 9.4 - 9.3 - 6.8 -16.2 -10.4 - 5.4 - 5.2 -10.3 -14.9 -10.9 -10.4 -14.8 - 8.6 -17.2 -14.0 -19.0 -17.5 -18.4 -16.9 -17.7 -17.2 -15.5 -22.4 -24.4 -14.4 - 8.8 X16.4 -19.6 -22.3 -21.8 -20.1 -19.3 -18.6 -18.2 -16.8 -20.6 -26.1 -25.4 -24.4 -22.3 -22.6 -27.5 -23.2 600 to 750 km. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 - 1.8 - 3.5 9.9 11.3 6.7 8.0 15.1 10.5 0.4 -3.7 7.8 10.6 7.1 2.9 8.9 1.4 0.5 4.1 - 3.5 - 1.5 8.1 11.8 7.8 2.3 7.5 9.4 9.9 2.7 9.8 12.4 5.0 11.6 7.1 5.2 15.6 3.6 15.0 9.9 5.6 9.9 9.2 10.4 11.6 16,9 4.8 6.8 10.2 9.3 10.5 12.4 4.2 12.3 14.2 3.3 17.0 12.3 2.9 11.7 10,8 13.2 12.1 19.6 7.2 7.9 11.6 11.7 12.7 13.3 5.6 9.5 6.1 13.9 12.6 10.6 7.5 7.7 10.2 9.7 6.5 3.7 8.7 5.0 3.9 5.7 5.9 5.6 0.2 6.0 2.9 10.0 - 4.7 - 6.6 1.5 - 4.9 - 7,7 1.5 1.7 -11.3 - 2.6 4.3 - 1.8 - 3.7 - 7.6 - 7.1 0.4 2.3 - 5.1 3.1 - 8.5 - 7.9 -10.9 - 9.0 - 9.1 - 4.6 -10.6 -12.2 - 6.0 - 2.7 - 3.5 - 6.6 -10.0 - 9.5 - 0.8 -13,1 -10.9 - 9.3 -15.7 -16.7 -10.5 -19.5 -19.5 -18.3 - 9.3 -12.8 -19.9 -15.0 -14.7 -10.7 -22.1 -11.6 -23.4 -19.5 -17.1 -23.1 -21.8 -25.0 -20.8 -19.2 -20.6 -21.9 -21.2 -16.2 -21.3 -21.2 -25.0 -19.1 - 3.1 -17.7 - 8.0 - 9.2 - 4.1 -15.9 ~3 r TABLE III continued 800 to 900 km. 1 2 3 4 5 6 7 8 9 10 5.6 4.6 - 1.4 1.7 4.9 7.4 5.5 2.7 11.8 0.0 9.6 5.3 - 1.0 3.8 12.2 6.9 10.4 6.2 13.5 4.5 10.8 4.4 7,9 10.8 5.9 14.6 12.4 7.2 10.9 13.9 13.7 7.6 21.4 14.5 9.7 14.2 10.4 17.0 10.5 7.8 7.9 5.6 16.1 10.6 6.9 4.7 4.6 4.2 8.8 3.9 - 3.2 -3.4 -11.5 - 9.2 - 3.8 - 2.5 - 2.3 - 3.7 - 1.0 -4.8 - 8.1 - 7.7 -12.3 - 8.3 - 8.5 -10.3 -14.7 - 5.6 -10.7 - 7.5 -19.0 -15.6 -17.5 - 8.6 -17.3 -23.9 -17.1 -14.9 -16.4 P-16.3 -'21.8 -15.7 -21.5 -24.2 -12.0 -15.5 -22.3 -24.9 -26.0 -19.8 11 16.3 12 0.4 15.7 8.2 10.8 - 1.7 -11.8 7.1 8.4 10.9 - 1.1 - 6.3 -14,8 -16.2 -25.8 -14.6 -18.5 -22.1 1000 kmn. to 1200 km. 1 2 3 4 5 6 7 2.7 5.1 12.0 5.8 - 4.6 0.2 7.1 5.0 10.6 14.0 4.3 6.4 1.6 10.1 13.2 3.8 6.3 14.2 14.2 11.4 7.5 13.2 14.3 - 5.2 1.9 12.7 9.1 2.9 - 5.4 0.6 - 7.4 - 8.1 - 5.1 - 8.8 -10.0 - 9,4 -21.8 -10.5 -18.2 -13.6 -11.5 -21.9 -18.5 -16.9 -21,9 -16.7 4.9 5.1 12.8 4.0 - 2.4 6.4 9.9 7.7 14.9 - 3.4 -10.3 -13.7 -21.6 - 7.9 -15.1 -22.7 1300 km. to 1600 km. I 2 3 4 5 - 1.7 0.6 3.1 9.0 - 2.5 1.7 3.1 13.0 11.4 6.5 6.7 6.6 13.3 13.0 12.9 8.8 10.5 7.2 17.7 8.8 7,0 17.2 16.0 9.5 1.7 1.4 4.7 6.3 1.2 2.8 - 7.0 - 9.7 -14.6 -10.0 - 6.3 -10.6 -10.9 -18,9 -17.1 -11.8 -13.1 -20,5 -24.0 -24.4 -26.4 5000 km. to 6000 km. 1 2 3 4 7.6 5.3 5.8 2.4 11.7 5.1 15.4 3.9 13.2 12.4 12.5 11.6 12.6 15.6 12.9 17.0 14.1 11,4 3.9 8.4 - 1.1 0.6 - 6.0 1.6 - 7.5 - 8.4 -10.4 -11.1 -14.3 -12.1 - 9.7 -16.8 -23.5 -20.2 -20.5 -21.0 8000 km. 1 2 3 3.1 - 2.6 - 2.9 1.2 1.9 5.8 16.2 6.0 9.5 12.6 10.4 10.5 11.9 - 1.3 - 5.7 10.0 - 6.6 - 6.1 12.1 15.6 - 7.9 -16.5 -16.5 -11.6 -22.8 -11.6 -19.1 TABLE IV A0 in Star 4005.27 4012.50 1024. 4C4U. 23 4C33. 65 4CC7.08 4071.75 4077.88 4101.76 4119.C5 4127.83 4132.42 4154.42 415. 53 4161.'7 41].63.76 1187.36 4191.63 4198.66 4205.26 4215.83 4227.19 4233.43 4236.08 4242.78 424 x.18 4250.70 4254.t3 4258.49 4260.60 4271.74 4275.30 4282.83 4290.07 4294.51 4299.93 4305.84 4314.80 4321.08 4o3. 65 Rewland 4005.44 4012.51 4024996.015.88 4063.71 "1036.91 4071.89 4077.34 4101.88 4118S85 4127.86 4132.49 4154.49 4156.62 4161.55 416:. 32 4187.56 4191.68 4198.71 4205.26 7215.90 4227.01 4233.45 4236.16 4242.70 4247.28 4250.64 4254.51 4258.73 420. 53 4271.78 4274.91 4282.83 4289.92 4294.42 4300.12 4305.92 4314.85 4320.99 4325.68 Fe Ti4 Ti4 Fe Fe V 4 Ce Ce Ni+ Fe Fe Sr H6 -Co Fe Identification V Fe Fe FT Zr Ti Ce Nd Ti+ Cr Fe Ti Fe Ce Fe V Eu 'Vi4 Sr+ Ca Fe+ Cr4 V Y+ e Zr Crt Mnt Ert Pe Sc+ Fe Cr Zr+ Fe4 Fe Fe Cr Ca T i Tit Fe Ti n n4 Ce S' Ti Sc Pr Sc4 Tip Sc+ F? Nd -37 - TABLE TIV (Ccrtti/yiked) A.~in Sta..' 45330. 7 6 4337. " 4340.66 4 31. 44.. 4 368. 00 4374.86 43383. 58 4400.65 4404., 94 4408.6. 4415.28 4435.43 4443.61 4455.05 4461.73 4463.21I 4LV1"41 4633.91 1549.63 4554.23 4563.81 4571.92 4563.58 48 3.2 4855.60 41313 Poth, land. 430.8? 4337.69 4340.63 43F"44. 60 43591.81 1367.8 4 4374.69 4383.63 4IK.4 3 -4104. 95 4408-.55 4415.24 4455.43 4443.66 44 54..96 4461. 90 4469. 08 4501.45 4633.90 4549.77 4554.26 1563.94 4972. 11 4583.82 3 4824.33 4P55660 4861.53 Ti+ mi Cr Mg -dentificatico s c+ "7 * V rr r4-; Fe V Ti " TEu C:? Zr Fe rn' + m..1 Ti Co Tj?4. Few Co Bay Zr rr 4' Fe Vt 0,2~La V -38 - TAB E V 20 Lines Due to Ionized Atoms Used to Isolate the Ionization Effect on Radial Velocity. Group 7;.in Star 1 2 3 4 5 6 4258.49 4368.00 4374.86 4163.76 4187.36 42 36.08 4242. 78 4314.80 4321.08 4337.77 4400.65 4294.51 4299.93 4583.58 4468.91 4501.41 4549.63 4077.88 4215.83 4247.18 Identification Zr+ Fe+ Ti+ Sc+ Ti+ Cr Fe Ti Ni+ V Y+Fe Zr Cr+ Mi+ T7.r+ Fe Sc+ Ti+ Sc+ Ti+ Sc+ V Ti+ Fe Ti+ Mn+ Ce Fe V+ Ti+ Ti+ Ti+ Fe+ Co Sr+ Sr+ Sc+ PLATE I. RADIAL VELOCITY CURVES OF 7[AQUILAE Upper Left. Curve, Mean of All Levels Following Curves, Seiren Arbitrary Levels in Order of Height C - I -4000 0 0 DA+32 0LT 0I VEOCT DIFERECE Deitin pf Seeifrn eesfo h t~ea of ll Lvel 0pC j~7r-. b ~~Q~L-t-t /L~-$ 0 -41 - PLATE III. VELOCITY DIFFERENCES OBTAINED FROM NEUTRAL ATOMS Two-minus-one, Three-minus-two, Four-minus-three -42 - KM OO[ +3 -OO 00 S0 0 0 00 000 000 0 0 o 0 0 0 -3 0 0 0 0 0- -,....0 0 0 o 0 S00 0 +3\ So ~ --3 03 - 0-0-~ oo0 oo oo 0 0 0 0, oo o........ IOIZED ATOMS Deviations of Five Levels from the Lowest Level Deiaios f iv evlsfrm th,owstLee I -43 - PLATE V. VELOCITY DIPFFPMENCES, IONIZED MII US NEUTRAL For First, Second and Third Levels Fourth Curve, Mean of All Ionized Minus Mean of All Neutral 'R ,. t 1,. 1 ~ 4 rte,, ' r J., r:Y i ' I y ' R.t h r r, V, J,, Y I. r; ..s":.;..;+,-,;r.., any' Y.e ( f P< S _ 4, '.^[ } yy /iy 'f 1 4-3 ' r f. ^ ' A / t T' 'w A~1 Y I L.{ e' ^.W +f y' Y " ' ' IG: 7 A~ i _ s d ' +. ry Y _ _ N p " A: '; 4 t 1 r,r } 1p Yk;: s.,_: y z,. ~,., V, k yFVYn " J r7. " o- 31Rk" $, fro a' _ i,? r ' w., ',,, { i *' e ' t E M t b r Y fit x' 'qA MxA' ', t' ' * ' hr n f uF ' { _ a L. - s s. _ 3d L..,.. l9 /i./:s 't r:F yb''.y. f ' tK o " J. '..tom E,,, Y ', ',: ' UNi\\i\\\1VER1\\\\\1lf\\l F MAiIhUAINg #. '.t Y _ y 3. - ',.... ar. d, w y " k.. # t, tiem t.: a. p S. V u k. ";, ". ", r b'r i, 5 y _ t,.. - f...' r.,,' - o, K a. 'ka r _,. r'fi A, a t i.. P p = l la? r R J t 1+ SA,; ' _ f a. a w. F, ~!_ _ i a a ' r. ' x w F PYyc d e a -K. 3 r q 'fi Y _..,d. w q -, ". -".., ': G any " 9 ar. ",.t: _ _ "a. < "1_. _^.. s ",, ~tYs, ~ - Y y, d y,,. i mot..;r =.". ' _ ' - " ' ',,?d,'a F;'. 44 A T, tt''' fr." ^ ~f,,, s^ a F - ',,: ter. "s+.q rv "~5 _ ~ -, - ' ~ ". e 'a%.4 r;.. a.s t~ d:- "t,,ha.r ", y, p, -,tp __.. r t'., r ',y a lie q..?5m w 1 " - ~ '"'+....... n. ' '5W" " - " "^. ^:'N h V. ^Yn, 'sif.l y a n~ 'E A, $W;i.e. RTJndNr,. k,f