Red giant stellar collisions in the Galactic Centre
(2009) In Monthly Notices of the Royal Astronomical Society 393(3). p.1016-1033- Abstract
- We show that collisions with stellar-mass black holes can partially explain the absence of bright giant stars in the Galactic Centre, first noted by Genzel et al. We show that the missing objects are low-mass giants and asymptotic giant branch stars in the range 1-3 M-circle dot. Using detailed stellar evolution calculations, we find that to prevent these objects from evolving to become visible in the depleted K bands, we require that they suffer collisions on the red giant branch, and we calculate the fractional envelope mass losses required. Using a combination of smoothed particle hydrodynamic calculations, restricted three-body analysis and Monte Carlo simulations, we compute the expected collision rates between giants and black holes,... (More)
- We show that collisions with stellar-mass black holes can partially explain the absence of bright giant stars in the Galactic Centre, first noted by Genzel et al. We show that the missing objects are low-mass giants and asymptotic giant branch stars in the range 1-3 M-circle dot. Using detailed stellar evolution calculations, we find that to prevent these objects from evolving to become visible in the depleted K bands, we require that they suffer collisions on the red giant branch, and we calculate the fractional envelope mass losses required. Using a combination of smoothed particle hydrodynamic calculations, restricted three-body analysis and Monte Carlo simulations, we compute the expected collision rates between giants and black holes, and between giants and main-sequence stars in the Galactic Centre. We show that collisions can plausibly explain the missing giants in the 10.5 < K < 12 band. However, depleting the brighter (K < 10.5) objects out to the required radius would require a large population of black hole impactors which would in turn deplete the 10.5 < K < 12 giants in a region much larger than is observed. We conclude that collisions with stellar-mass black holes cannot account for the depletion of the very brightest giants, and we use our results to place limits on the population of stellar-mass black holes in the Galactic Centre. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1372123
- author
- Dale, James E. LU ; Davies, Melvyn B LU ; Church, Ross P. LU and Freitag, Marc
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- stars: late-type, Galaxy: centre
- in
- Monthly Notices of the Royal Astronomical Society
- volume
- 393
- issue
- 3
- pages
- 1016 - 1033
- publisher
- Oxford University Press
- external identifiers
-
- wos:000263359300025
- scopus:60349122937
- ISSN
- 1365-2966
- DOI
- 10.1111/j.1365-2966.2008.14254.x
- language
- English
- LU publication?
- yes
- id
- 19729448-f155-43fd-b14a-a71d8fd44bf4 (old id 1372123)
- date added to LUP
- 2016-04-01 12:11:39
- date last changed
- 2024-04-09 04:07:24
@article{19729448-f155-43fd-b14a-a71d8fd44bf4, abstract = {{We show that collisions with stellar-mass black holes can partially explain the absence of bright giant stars in the Galactic Centre, first noted by Genzel et al. We show that the missing objects are low-mass giants and asymptotic giant branch stars in the range 1-3 M-circle dot. Using detailed stellar evolution calculations, we find that to prevent these objects from evolving to become visible in the depleted K bands, we require that they suffer collisions on the red giant branch, and we calculate the fractional envelope mass losses required. Using a combination of smoothed particle hydrodynamic calculations, restricted three-body analysis and Monte Carlo simulations, we compute the expected collision rates between giants and black holes, and between giants and main-sequence stars in the Galactic Centre. We show that collisions can plausibly explain the missing giants in the 10.5 < K < 12 band. However, depleting the brighter (K < 10.5) objects out to the required radius would require a large population of black hole impactors which would in turn deplete the 10.5 < K < 12 giants in a region much larger than is observed. We conclude that collisions with stellar-mass black holes cannot account for the depletion of the very brightest giants, and we use our results to place limits on the population of stellar-mass black holes in the Galactic Centre.}}, author = {{Dale, James E. and Davies, Melvyn B and Church, Ross P. and Freitag, Marc}}, issn = {{1365-2966}}, keywords = {{stars: late-type; Galaxy: centre}}, language = {{eng}}, number = {{3}}, pages = {{1016--1033}}, publisher = {{Oxford University Press}}, series = {{Monthly Notices of the Royal Astronomical Society}}, title = {{Red giant stellar collisions in the Galactic Centre}}, url = {{http://dx.doi.org/10.1111/j.1365-2966.2008.14254.x}}, doi = {{10.1111/j.1365-2966.2008.14254.x}}, volume = {{393}}, year = {{2009}}, }