Results 71 to 80 of about 12,147 (249)

Evidence for Mass-dependent Evolution of Transitional Dwarf Galaxies in the Virgo Cluster

The Astrophysical Journal
The presence of transitional dwarf galaxies in cluster environments supports the hypothesis that infalling star-forming galaxies are transformed into quiescent early-type dwarf galaxies (ETdGs) through environmental effects.
Suk Kim, Soo-Chang Rey, Youngdae Lee
doaj   +1 more source

Stellar Abundances in Dwarf Irregular Galaxies

, 2003
Dwarf irregular galaxies appear to have undergone very slow chemical evolution since they have low nebular abundances, but have had ongoing star formation over the past 15 Gyr. They are too distant for red giant abundance analyses to examine the details of their chemical evolution, however the isolated, bright blue supergiants do allow us to determine ...
Venn, K.A., Tolstoy, E., Kaufer, A., Kudritzki, R.P.   +3 more
openaire   +3 more sources

AT 2017fvz: a nova in the dwarf irregular galaxy NGC 6822 [PDF]

Monthly Notices of the Royal Astronomical Society, 2019
ABSTRACT A transient in the Local Group dwarf irregular galaxy NGC 6822 (Barnard’s Galaxy) was discovered on 2017 August 2 and is only the second classical nova discovered in that galaxy. We conducted optical, near-ultraviolet, and X-ray follow-up observations of the eruption, the results of which we present here.
W Zheng, S C Williams, K L Page, P A James, J C Hestenes, M Henze, A V Filippenko, C M Copperwheat, M J Darnley, M W Healy   +9 more
openaire   +5 more sources

Mass‐Loss, Composition and Observational Signatures of Stellar Winds From X‐Ray Bursts

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT X‐Ray bursts (XRBs) are powerful thermonuclear events on the surface of accreting neutron stars (NSs), which can synthesize intermediate‐mass elements. Although the high surface gravity prevents an explosive ejection, a small fraction of the envelope may be ejected by radiation‐driven winds.
Yago Herrera, Daniel Muñoz Vela, Gloria Sala, Jordi José, Yuri Cavecchi   +4 more
wiley   +1 more source

Chemodynamical Simulations of Dwarf Galaxy Evolution

Advances in Astronomy, Volume 2014, Issue 1, 2014., 2014
In this review I give a summary of the state of the art for what concerns the chemo‐dynamical numerical modelling of galaxies in general and of dwarf galaxies in particular. In particular, I focus my attention on (i) initial conditions, (ii) the equations to solve; (iii) the star formation process in galaxies, (iv) the initial mass function, (v) the ...
Simone Recchi, José Manuel Vílchez Medina   +1 more
wiley   +1 more source

Identifying Old Tidal Dwarf Irregulars [PDF]

, 2000
We examine the observational consequences of the two possible origins for irregular galaxies: formation from collapse of a primordial cloud of gas early in the age of the Universe, and formation from tidal tails in an interaction that could have occured ...
Bottinelli L., Broeils A. H., de Blok W. J. G., Deidre A. Hunter, Duc P.-A., Edmunds M. G., Erin W. Roye, Ferraro F. R., Israel F., Lee H., McIntyre V. J., Mirabel I. F., Mirabel I. F., Sally D. Hunsberger, Skillman E. D., Tully R. B., Zwicky F.   +16 more
core   +3 more sources

HST FUV Spectroscopy of Super Star Cluster A in the Green Pea Analog Mrk 71: Revealing the Presence of Very Massive Stars

The Astrophysical Journal, 2023
Mrk 71 is a low-metallicity ( Z = 0.16 Z _☉ ) starburst region in the local dwarf galaxy NGC 2366, hosting two super star clusters (SSCs A and B), and it is recognized as a Green Pea (GP) analog with SSC A responsible for the GP properties.
Linda J. Smith, M. S. Oey, Svea Hernandez, Jenna Ryon, Claus Leitherer, Stephane Charlot, Gustavo Bruzual, Daniela Calzetti, You-Hua Chu, Matthew J. Hayes, Bethan L. James, Anne E. Jaskot, Göran Östlin   +12 more
doaj   +1 more source

Chemical evolution of dwarf irregular and blue compact galaxies [PDF]

Astronomy & Astrophysics, 2011
Dwarf irregular and blue compact galaxies are very interesting objects since they are relatively simple and unevolved. We present new models for the chemical evolution of these galaxies by assuming different regimes of star formation (bursting and continuous) and different kinds of galactic winds (normal and metal-enhanced).
Yin, J., MATTEUCCI, MARIA FRANCESCA, Vladilo, G.   +2 more
openaire   +5 more sources

Commodity risk assessment of Betula pendula and Betula pubescens plants from the UK

EFSA Journal, Volume 22, Issue 11, November 2024.
Abstract The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as ‘High risk plants, plant products and other objects’. This Scientific Opinion covers plant health risks posed by plants of Betula pendula and B.
EFSA Panel on Plant Health (PLH), Antonio Vicent Civera, Paula Baptista, Anna Berlin, Elisavet Chatzivassiliou, Jaime Cubero, Nik Cunniffe, Eduardo de la Peña, Nicolas Desneux, Francesco Di Serio, Anna Filipiak, Beata Hasiów‐Jaroszewska, Hervé Jactel, Blanca B. Landa, Lara Maistrello, David Makowski, Panagiotis Milonas, Nikos T. Papadopulos, Roel Potting, Hanna Susi, Dirk Jan Van Der Gaag, Andrea Battisti, Claude Bragard, Christer Sven Magnusson, Hugo Mas, Daniel Rigling, Massimo Faccoli, Alžběta Mikulová, Fabio Stergulc, Eugen Christoph, Olaf Mosbach‐Schulz, Franz Streissl, Paolo Gonthier   +32 more
wiley   +1 more source

Astronomical Signatures of Dark Matter

Advances in High Energy Physics, Volume 2014, Issue 1, 2014., 2014
Several independent astronomical observations in different wavelength bands reveal the existence of much larger quantities of matter than what we would deduce from assuming a solar mass to light ratio. They are very high velocities of individual galaxies within clusters of galaxies, higher than expected rotation rates of stars in the outer regions of ...
Paul Gorenstein, Wallace Tucker, Anselmo Meregaglia   +2 more
wiley   +1 more source