II/40 Hydrogen-Line Absorption in Early-Type Stars (Bappu+ 1962)
Photoelectric Measures of Hydrogen-Line Absorption in Early-Type Stars
Bappu M.K.V., Chandra S., Sanwal N.B., Sinvhal S.D.
<Mon. Not. R. Astron. Soc., 123, 521 (1962)>
=1962MNRAS.123..521B 1962MNRAS.123..521B
ADC_Keywords: Photometry, hydrogen-line; Stars, early-type
Abstract:
Photoelectric determinations of H-γ absorption line intensity
have been made of stars in selected clusters and associations as well
as in the general galactic field. Interference filters having a width
at half intensity of 45Å were used to isolate spectral regions
centered on 4280Å, H-γ and 4410Å. The Γ indices
derived, which represent a measure of H-γ absorption, can be
used in conjunction with unreddened values of either (U-B) or (B-V)
for spectral and luminosity class determinations of stars in the
spectral range O6 to A0.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
data.dat 79 177 Γ values (from table II of paper)
--------------------------------------------------------------------------------
Byte-by-byte Description of file (#): data.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Star Star identification (HD or cluster star number)
23- 25 I3 cmag V0 ? Dereddened V0 magnitude
32- 35 I4 cmag (U-B)0 ? Dereddened (U-B)0 color index
43- 45 I3 --- Gamma Γ index (1)
77- 79 I3 --- ID [0/177] Running number
--------------------------------------------------------------------------------
Note (1): Γ * 10-3 = -2.5 * log[(L*S)(1/2)/γ]
where L, S and γ indicate the respective deflections through the
filters that isolate respectively the continuum on the long and short
sides and the radiation at the position of the Hγ line.
--------------------------------------------------------------------------------
History:
* October 1972: keypunched at Institut d'Astronomie de Lausanne (Switzerland)
* 19-Dec-1996: standarized by Julie Anne Watko [SSDOO/ADC]
* 11-Jan-2017: star name completed for missing HD designations
(End) Julie Anne Watko [SSDOO/ADC] 19-Dec-1996