scholarly journals Pixel Lensing: The Key to the Universe

1996 ◽  
Vol 173 ◽  
pp. 365-370
Author(s):  
Andrew Gould
Keyword(s):  
Event Rate ◽  
Virgo Cluster ◽  
Star Formation History ◽  
Powerful Method ◽  
Suppression Factor ◽  
Photon Detection ◽  
Formation History ◽  
History Of ◽  
The Universe

Pixel lensing, the gravitational microlensing of unresolved stars, is potentially a powerful method for detecting and measuring microlensing events. Two groups are currently refining this method in observations toward M31. I show that the technique has wide application, from searching for intra-cluster Machos in the Virgo cluster, to improving the accuracy of follow-up observations of Galactic microlensing events, to measuring the star-formation history of the universe. I derive the equation for the pixel lensing event rate where Qmin is the minimum signal to noise for detection, τ is the optical depth, Nres is the number of telescope resolution elements in the field, is the photon detection rate from a fluctuation magnitude star, and ξ is a suppression factor.

scholarly journals The Luminosity Function of White Dwarfs in the Local Disk and Halo

1989 ◽  
Vol 114 ◽  
pp. 15-23 ◽  
Author(s):  
James Liebert ◽  
Conard C. Dahn ◽  
David G. Monet
Keyword(s):  
White Dwarfs ◽  
Luminosity Function ◽  
Solar Neighborhood ◽  
Star Formation History ◽  
Empirical Estimates ◽  
Formation History ◽  
History Of ◽  
Cool White Dwarfs ◽  
Local Disk

The luminosity function (LF) and total space density of white dwarfs in the solar neighborhood contain important information about the star formation history of the stellar population, and provide an independent method of measuring its age. The first empirical estimates of the LF for degenerate stars were those of Weidemann (1967), Kovetz and Shaviv (1976) and Sion and Liebert (1977). The follow-up investigations made possible by the huge Luyten Palomar proper motion surveys, however, added many more faint white dwarfs to the known sample. While the number of known cool white dwarfs grew to nearly one hundred, these did not include any that were much fainter intrinsically than the coolest degenerates found from the early Luyten, van Biesbroeck and Eggen-Greenstein lists.

scholarly journals HUBBLE SPACE TELESCOPEGRISM SPECTROSCOPY OF EXTREME STARBURSTS ACROSS COSMIC TIME: THE ROLE OF DWARF GALAXIES IN THE STAR FORMATION HISTORY OF THE UNIVERSE

2014 ◽  
Vol 789 (2) ◽  
pp. 96 ◽  
Author(s):  
Hakim Atek ◽  
Jean-Paul Kneib ◽  
Camilla Pacifici ◽  
Matthew Malkan ◽  
Stephane Charlot ◽  
...  
Keyword(s):  
Star Formation ◽  
Dwarf Galaxies ◽  
Cosmic Time ◽  
Star Formation History ◽  
Formation History ◽  
History Of ◽  
The Universe

scholarly journals Cosmic Star Formation from the Milky Way and its Satellites

1999 ◽  
Vol 190 ◽  
pp. 8-14
Author(s):  
F.D.A. Hartwick
Keyword(s):  
Star Formation ◽  
Star Formation Rate ◽  
Formation Rate ◽  
Star Formation History ◽  
Evolutionary Models ◽  
Disk Mass ◽  
Formation History ◽  
History Of ◽  
The Universe

We use observations and evolutionary models of local objects to interpret a recent determination of the star-formation history of the universe. By fitting the global star-formation rate, the model predicts the ratio of spheroid to disk mass of ~1, an intergalactic medium (IGM) whose mass is ~2.3 times the mass in stars, and whose metallicity is ~0.1 Z⊙.

scholarly journals The star-formation history of the Universe from the stellar populations of nearby galaxies

Nature ◽  
2004 ◽  
Vol 428 (6983) ◽  
pp. 625-627 ◽  
Author(s):  
Alan Heavens ◽  
Benjamin Panter ◽  
Raul Jimenez ◽  
James Dunlop
Keyword(s):  
Star Formation ◽  
Stellar Populations ◽  
Star Formation History ◽  
Formation History ◽  
History Of ◽  
Nearby Galaxies ◽  
The Universe

scholarly journals A gamma-ray determination of the Universe’s star formation history

Science ◽  
2018 ◽  
Vol 362 (6418) ◽  
pp. 1031-1034 ◽  
Author(s):  
Keyword(s):  
Star Formation ◽  
Gamma Ray ◽  
Cosmic Time ◽  
Star Formation History ◽  
Large Area ◽  
Extragalactic Background Light ◽  
Galaxy Surveys ◽  
Formation History ◽  
History Of ◽  
The Universe

The light emitted by all galaxies over the history of the Universe produces the extragalactic background light (EBL) at ultraviolet, optical, and infrared wavelengths. The EBL is a source of opacity for gamma rays via photon-photon interactions, leaving an imprint in the spectra of distant gamma-ray sources. We measured this attenuation using 739 active galaxies and one gamma-ray burst detected by the Fermi Large Area Telescope. This allowed us to reconstruct the evolution of the EBL and determine the star formation history of the Universe over 90% of cosmic time. Our star formation history is consistent with independent measurements from galaxy surveys, peaking at redshiftz~ 2. Upper limits of the EBL at the epoch of reionization suggest a turnover in the abundance of faint galaxies atz~ 6.

scholarly journals The role of massive halos in the star formation history of the Universe

2015 ◽  
Vol 579 ◽  
pp. A132 ◽  
Author(s):  
P. Popesso ◽  
A. Biviano ◽  
A. Finoguenov ◽  
D. Wilman ◽  
M. Salvato ◽  
...  
Keyword(s):  
Star Formation ◽  
Star Formation History ◽  
Formation History ◽  
History Of ◽  
Massive Halos ◽  
The Universe

scholarly journals The 0.4 $\mathsf{<}$ z $\mathsf{<}$ 1.3 star formation history of the Universe as viewed in the far-infrared

2009 ◽  
Vol 496 (1) ◽  
pp. 57-75 ◽  
Author(s):  
B. Magnelli ◽  
D. Elbaz ◽  
R. R. Chary ◽  
M. Dickinson ◽  
D. Le Borgne ◽  
...  
Keyword(s):  
Star Formation ◽  
Far Infrared ◽  
Star Formation History ◽  
Formation History ◽  
History Of ◽  
The Universe

scholarly journals The star-formation history of the Universe with the SKA

2015 ◽  
Author(s):  
Matt Jarvis ◽  
Nick Seymour ◽  
Jose Afonso ◽  
P. N. Best ◽  
Rob J. Beswick ◽  
...  
Keyword(s):  
Star Formation ◽  
Star Formation History ◽  
Formation History ◽  
History Of ◽  
The Universe
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