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Full-Text Articles in Physical Sciences and Mathematics
The Cluster And Field Galaxy Active Galactic Nucleus Fraction At Z = 1-1.5: Evidence For A Reversal Of The Local Anticorrelation Between Environment And Agn Fraction, Paul Martini, E. D. Miller, M. Brodwin, S. A. Stanford, Anthony H. Gonzalez, M. Bautz, R. C. Hickox
The Cluster And Field Galaxy Active Galactic Nucleus Fraction At Z = 1-1.5: Evidence For A Reversal Of The Local Anticorrelation Between Environment And Agn Fraction, Paul Martini, E. D. Miller, M. Brodwin, S. A. Stanford, Anthony H. Gonzalez, M. Bautz, R. C. Hickox
Dartmouth Scholarship
The fraction of cluster galaxies that host luminous active galactic nuclei (AGNs) is an important probe of AGN fueling processes, the cold interstellar medium at the centers of galaxies, and how tightly black holes and galaxies co-evolve. We present a new measurement of the AGN fraction in a sample of 13 clusters of galaxies (M >= 1014 M ⊙) at 1 < z < 1.5 selected from the Spitzer/IRAC Shallow Cluster Survey, as well as the field fraction in the immediate vicinity of these clusters, and combine these data with measurements from the literature to quantify the relative evolution of cluster and field AGN from the present to z ~ 3. We estimate that the cluster AGN fraction at 1 < z < 1.5 is f_A = 3.0^{+2.4}_{-1.4}% for AGNs with a rest-frame, hard X-ray luminosity greater than L X, H >= 1044 erg s-1. This fraction is measured relative to all cluster galaxies more luminous than M^*_{3.6}(z) + 1, where M^*_{3.6}(z) is the absolute magnitude of the break in the galaxy luminosity …
Multi-Wavelength Observations Of Supernova 2011ei: Time-Dependent Classification Of Type Iib And Ib Supernovae And Implications For Their Progenitors, Dan Milisavljevic, Raffaella Margutti, Alicia M. Soderberg, Giuliano Pignata, Laura Chomiuk, Robert A. Fesen
Multi-Wavelength Observations Of Supernova 2011ei: Time-Dependent Classification Of Type Iib And Ib Supernovae And Implications For Their Progenitors, Dan Milisavljevic, Raffaella Margutti, Alicia M. Soderberg, Giuliano Pignata, Laura Chomiuk, Robert A. Fesen
Dartmouth Scholarship
We present X-ray, UV/optical, and radio observations of the stripped-envelope, core-collapse supernova (SN) 2011ei, one of the least luminous SNe IIb or Ib observed to date. Our observations begin with a discovery within 1 day of explosion and span several months afterward. Early optical spectra exhibit broad, Type II-like hydrogen Balmer profiles that subside rapidly and are replaced by Type Ib-like He-rich features on the timescale of one week. High-cadence monitoring of this transition suggests that absorption attributable to a high velocity (> 12,000 km/s) H-rich shell is not rare in Type Ib events. Radio observations imply a shock velocity …