Results 31 to 40 of about 54,114 (300)

Pre-Processing and Post-Processing in Group-Cluster Mergers [PDF]

, 2013
Galaxies in clusters are more likely to be of early type and to have lower star formation rates than galaxies in the field. Recent observations and simulations suggest that cluster galaxies may be `pre-processed' by group or filament environments and ...
Ricker, Paul M., Vijayaraghavan, Rukmani
core   +1 more source

Growing the first galaxies’ merger trees

Monthly Notices of the Royal Astronomical Society, 2023
ABSTRACT Modelling the growth histories of specific galaxies often involves generating the entire population of objects that arise in a given cosmology and selecting systems with appropriate properties. This approach is highly inefficient when targeting rare systems such as the extremely luminous high-redshift galaxy candidates detected ...
Ethan O Nadler, Andrew Benson, Trey Driskell, Xiaolong Du, Vera Gluscevic   +4 more
openaire   +2 more sources

Identifying Galaxy Mergers in Simulated CEERS NIRCam Images Using Random Forests

The Astrophysical Journal, 2023
Identifying merging galaxies is an important—but difficult—step in galaxy evolution studies. We present random forest (RF) classifications of galaxy mergers from simulated JWST images based on various standard morphological parameters.
Caitlin Rose, Jeyhan S. Kartaltepe, Gregory F. Snyder, Vicente Rodriguez-Gomez, L. Y. Aaron Yung, Pablo Arrabal Haro, Micaela B. Bagley, Antonello Calabró, Nikko J. Cleri, M. C. Cooper, Luca Costantin, Darren Croton, Mark Dickinson, Steven L. Finkelstein, Boris Häußler, Benne W. Holwerda, Anton M. Koekemoer, Peter Kurczynski, Ray A. Lucas, Kameswara Bharadwaj Mantha, Casey Papovich, Pablo G. Pérez-González, Nor Pirzkal, Rachel S. Somerville, Amber N. Straughn, Sandro Tacchella   +25 more
doaj   +1 more source

Galaxy mergers and gravitational lens statistics [PDF]

The Astrophysical Journal, 1994
We investigate the impact of hierarchical galaxy merging on the statistics of gravitational lensing of distant sources. Since no definite theoretical predictions for the merging history of luminous galaxies exist, we adopt a parametrized prescription, which allows us to adjust the expected number of pieces comprising a typical present galaxy at z=0.65.
Rix, Hans-Walter, Maoz, Dan, Turner, Edwin L., Fukugita, Masataka   +3 more
openaire   +2 more sources

A complete catalogue of merger fractions in AGN hosts: No evidence for an increase in detected merger fraction with AGN luminosity

The Open Journal of Astrophysics, 2023
Despite the importance of Active Galactic Nuclei (AGN) in galaxy evolution, the mechanisms that fuel AGN activity remain poorly understood. Theoretical models suggest that major mergers of galaxies contribute strongly to AGN fuelling, particularly at ...
Carolin Villforth
doaj   +1 more source

FULLY COMPRESSIVE TIDES IN GALAXY MERGERS [PDF]

The Astrophysical Journal, 2009
The disruptive effect of galactic tides is a textbook example of gravitational dynamics. However, depending on the shape of the potential, tides can also become fully compressive. When that is the case, they might trigger or strengthen the formation of galactic substructures (star clusters, tidal dwarf galaxies), instead of destroying them.
Renaud, Florent, Boily, Christian, Naab, Thorsten, Theis, Christian   +3 more
openaire   +2 more sources

Back to the Green Valley: How to Rejuvenate an S0 Galaxy through Minor Mergers

Galaxies, 2015
About half of the S0 galaxies in the nearby Universe show signatures of recent or ongoing star formation. Whether these S0 galaxies were rejuvenated by the accretion of fresh gas is still controversial.
Michela Mapelli
doaj   +1 more source

Spectacular Shells in the Host Galaxy of the QSO MC2 1635+119 [PDF]

, 2007
We present deep HST/ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical. Our new images reveal dramatic shell structure indicative of a merger event in the relatively recent past ...
Alan Stockton, Bruno Jungwiert, Canalizo G., Chien Peng, Dunlop J. S., Dupraz C., Francois Schweizer, Gabriela Canalizo, Mark Lacy, Nicola Bennert, Taylor G. L.   +10 more
core   +3 more sources

Sersic properties of disc galaxy mergers [PDF]

Monthly Notices of the Royal Astronomical Society, 2006
Sersic parameters characterising the density profiles of remnants formed in collision-less disc galaxy mergers are obtained; no bulge is included in our simulations. For the luminous component we find that the Sersic index is n ~ (1.5,5.3) with ~ 3 +/- 1 and an effective radius of R_e ~ (1.6,12.9) kpc with ~ 5 +/- 3 kpc.
Aceves, H., Velazquez, H., Cruz, F.
openaire   +2 more sources

Dwarf galaxy merger-induced star formation rate: A case study of Mrk 1481

Bibechana
The merger of the galaxies serves as a trigger for the increase in the galaxy’s star formation rate (SFR), which can be quantified by observing the column density of the Hα line.
Daya Nidhi Chhatkuli, Sanjaya Paudel, Amrit Sedain, Binil Aryal   +3 more
doaj   +3 more sources