NDLI: OB stars in the Tycho-2 and 2MASS catalogues

Content Provider	Springer Nature Link
Author	Gontcharov, G. A.
Copyright Year	2008
Abstract	The Tycho-2 proper motions and five-band Tycho-2 and 2MASS photometry for approximately 2.5 million common stars have been used to select OB stars and to determine the extinction and photometric distance for each of them. We have selected 37 485 stars and calculated their reddenings based on their positions in the two-color V $_{T}$-H, J-Ks diagrams relative to the zero-age main sequence and the theoretical reddening line for B5 stars. Tests confirm that the selected stars belong to the spectral types O-B with a small admixture of later types. We calculate the extinction coefficient R and its variations with Galactic longitude based on the positions of the selected stars in the two-color B $_{T}$-V $_{T}$, V $_{T}$-Ks diagram. The interstellar extinction for each star is calculated as the product of the reddening found and the coefficient R. The extinction and its variations with Galactic longitude agree well with the extinction based on the model by Arenou et al. (1992). Calibration of the relation between the absolute magnitude and reduced proper motion V $_{T}$ − $$ A_{V_T } $$ + 5 + 5 log µ for Hipparcos stars has allowed us to calculate the absolute magnitudes and photometric distances for the selected stars. The distances found agree with those derived from the Hipparcos parallaxes within 500 pc. The distribution of the stars and the extinction variations with distance found show that the selected stars form an almost complete sample of stars with spectral types earlier than B5 within about 750 pc of the Sun. The sample includes many noticeably reddened stars in the first and second Galactic quadrants that are absent from the Hipparcos and Tycho Spectral Types Catalogues. This slightly changes the pattern of the distribution of OB stars compared to the classical pattern based on Hipparcos.
Starting Page	7
Ending Page	16
Page Count	10
File Format	PDF
ISSN	10637737
Journal	Astronomy Letters
Volume Number	34
Issue Number	1
e-ISSN	15626873
Language	English
Publisher	SP MAIK Nauka/Interperiodica
Publisher Date	2011-03-11
Publisher Place	Dordrecht
Access Restriction	One Nation One Subscription (ONOS)
Subject Keyword	Optical constants Galaxy (Milky Way) spiral arms star classification extinction coefficient Astrophysics and Astroparticles Astronomy, Observations and Techniques
Content Type	Text
Resource Type	Article
Subject	Astronomy and Astrophysics Space and Planetary Science

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Influence of the gould belt on interstellar extinction

Using the reduced proper motions of Tycho-2 stars with B-V from 0.75 to 1.25: Monte Carlo simulations

Red giant clump in the Tycho-2 catalogue

Kinematics of Tycho-2 red giant clump stars

Large-scale filaments associated with Milky Way spiral arms

Classical Cepheids and the spiral structure of the milky way

Inaccuracies in the spectral classification of stars from the Tycho-2 Spectral Type Catalogue

Kinematics of the outer pseudorings and the spiral structure of the Galaxy

Two populations of open star clusters in the Galaxy

OB stars in the Tycho-2 and 2MASS catalogues

Similar Documents

Influence of the gould belt on interstellar extinction

Using the reduced proper motions of Tycho-2 stars with B-V from 0.75 to 1.25: Monte Carlo simulations

Red giant clump in the Tycho-2 catalogue

Kinematics of Tycho-2 red giant clump stars

Large-scale filaments associated with Milky Way spiral arms

Classical Cepheids and the spiral structure of the milky way

Inaccuracies in the spectral classification of stars from the Tycho-2 Spectral Type Catalogue

Kinematics of the outer pseudorings and the spiral structure of the Galaxy

Two populations of open star clusters in the Galaxy

OB stars in the Tycho-2 and 2MASS catalogues