Mid-Infrared Selected Quasars I: Virial Black Hole Mass and Eddington Ratios

We provide a catalog of 391 mid-infrared-selected (MIR, 24$\mu$m) broad-emission-line (BEL, type 1) quasars in the 22 deg$^2$ SWIRE Lockman Hole field. This quasar sample is selected in the MIR from Spitzer MIPS with $S_{\rm 24} > 400\mu$Jy, jointly with an optical magnitude limit of r (AB) $<$ 22.5 for broad line identification. The catalog is based on MMT and SDSS spectroscopy to select BEL quasars, extends the SDSS coverage to fainter magnitudes and lower redshifts, and recovers a more complete quasar population. The MIR-selected quasar sample peaks at $z\sim$1.4, and recovers a significant and constant (20\%) fraction of extended objects with SDSS photometry across magnitudes, which was not included in the SDSS quasar survey dominated by point sources. This sample also recovers a significant population of $z 19.1$. We then investigate the continuum luminosity and line profiles of these MIR quasars, and estimate their virial black hole masses and the Eddington ratios. The SMBH mass shows evidence of downsizing, though the Eddington ratios remain constant at $1 < z < 4$. Compared to point sources in the same redshift range, extended sources at $z < 1$ show systematically lower Eddington ratios. The catalog and spectra are publicly available online.Comment: 72 pages, 27 figures, 16 tables; ApJ accepte

The VIMOS VLT Deep Survey: the faint type-1 AGN sample

We present the type-1 active galactic nuclei (AGN) sample extracted from the VIMOS VLT Deep Survey first observations of 21000 spectra in 1.75 square degree. This sample, which is purely magnitude limited, free of morphological or color selection biases, contains 130 broad line AGN (BLAGN) spectra with redshift up to 5. Our data are divided into a wide (Iab < 22.5) and a deep (Iab < 24) subsample containing 56 and 74 objects respectively. Because of its depth and selection criteria, this sample is uniquely suited to study the population of faint type-1 AGN. Our measured surface density (~ 472 +- 48 BLAGN per square degree with Iab < 24) is significantly higher than that of any other optically selected sample of BLAGN with spectroscopic confirmation. By applying a morphological and color analysis to our AGN sample we find that: (1)~23% of the AGN brighter than Iab=22.5 are classified as extended; this percentage increases to ~42% for those with z < 1.6; (2) a non-negligible fraction of our BLAGN are lying close to the color space area occupied by stars in u*-g' versus g'-r' color-color diagram. This leads us to the conclusion that classical optical ultraviolet preselection technique, if employed at such deep magnitudes (Iab=22.5) in conjuction with a preselection of point-like sources, can miss miss up to ~35% of the AGN population. Finally, we present a composite spectrum of our sample of objects. While the continuum shape is very similar to that of the SDSS composite at short wavelengths, it is much redder than it at lambda > 3000 A. We interpret this as due to significant contamination from emission of the host galaxies, as expected from the faint absolute magnitudes sampled by our survey.Comment: Accepted to A&A, 18 pages, 14 figure

Development of 2MASS Catalog Server Kit

We develop a software kit called "2MASS Catalog Server Kit" to easily construct a high-performance database server for the 2MASS Point Source Catalog (includes 470,992,970 objects) and several all-sky catalogs. Users can perform fast radial search and rectangular search using provided stored functions in SQL similar to SDSS SkyServer. Our software kit utilizes open-source RDBMS, and therefore any astronomers and developers can install our kit on their personal computers for research, observation, etc. Out kit is tuned for optimal coordinate search performance. We implement an effective radial search using an orthogonal coordinate system, which does not need any techniques that depend on HTM or HEALpix. Applying the xyz coordinate system to the database index, we can easily implement a system of fast radial search for relatively small (less than several million rows) catalogs. To enable high-speed search of huge catalogs on RDBMS, we apply three additional techniques: table partitioning, composite expression index, and optimization in stored functions. As a result, we obtain satisfactory performance of radial search for the 2MASS catalog. Our system can also perform fast rectangular search. It is implemented using techniques similar to those applied for radial search. Our way of implementation enables a compact system and will give important hints for a low-cost development of other huge catalog databases.Comment: 2011 PASP accepte

A UV to Mid-IR Study of AGN Selection

We classify the spectral energy distributions (SEDs) of 431,038 sources in the 9 sq. deg Bootes field of the NOAO Deep Wide-Field Survey (NDWFS). There are up to 17 bands of data available per source, including ultraviolet (GALEX), optical (NDWFS), near-IR (NEWFIRM), and mid-infrared (IRAC/MIPS) data, as well as spectroscopic redshifts for ~20,000 objects, primarily from the AGN and Galaxy Evolution Survey (AGES). We fit galaxy, AGN, stellar, and brown dwarf templates to the observed SEDs, which yield spectral classes for the Galactic sources and photometric redshifts and galaxy/AGN luminosities for the extragalactic sources. The photometric redshift precision of the galaxy and AGN samples are sigma/(1+z)=0.040 and sigma/(1+z)=0.169, respectively, with the worst 5% outliers excluded. Based on the reduced chi-squared of the SED fit for each SED model, we are able to distinguish between Galactic and extragalactic sources for sources brighter than I=23.5. We compare the SED fits for a galaxy-only model and a galaxy+AGN model. Using known X-ray and spectroscopic AGN samples, we confirm that SED fitting can be successfully used as a method to identify large populations of AGN, including spatially resolved AGN with significant contributions from the host galaxy and objects with the emission line ratios of "composite" spectra. We also use our results to compare to the X-ray, mid-IR, optical color and emission line ratio selection techniques. For an F-ratio threshold of F>10 we find 16,266 AGN candidates brighter than I=23.5 and a surface density of ~1900 AGN per deg^2.Comment: Submitted to ApJ, 35 pages, 17 figures, 2 table

Anyon exclusions statistics on surfaces with gapped boundaries

An anyon exclusion statistics, which generalizes the Bose-Einstein and Fermi-Dirac statistics of bosons and fermions, was proposed by Haldane[1]. The relevant past studies had considered only anyon systems without any physical boundary but boundaries often appear in real-life materials. When fusion of anyons is involved, certain `pseudo-species' anyons appear in the exotic statistical weights of non-Abelian anyon systems; however, the meaning and significance of pseudo-species remains an open problem. In this paper, we propose an extended anyon exclusion statistics on surfaces with gapped boundaries, introducing mutual exclusion statistics between anyons as well as the boundary components. Motivated by Refs. [2, 3], we present a formula for the statistical weight of many-anyon states obeying the proposed statistics. We develop a systematic basis construction for non-Abelian anyons on any Riemann surfaces with gapped boundaries. From the basis construction, we have a standard way to read off a canonical set of statistics parameters and hence write down the extended statistical weight of the anyon system being studied. The basis construction reveals the meaning of pseudo-species. A pseudo-species has different `excitation' modes, each corresponding to an anyon species. The `excitation' modes of pseudo-species corresponds to good quantum numbers of subsystems of a non-Abelian anyon system. This is important because often (e.g., in topological quantum computing) we may be concerned about only the entanglement between such subsystems.Comment: 36 pages, 14 figure

New W-prime signals at the LHC

We study the $W^{'}$ phenomenology in composite Higgs/ warped extra dimensional models focusing on the effect of fermionic resonances at $\sim$1 TeV. After deriving the existing bounds from the current LHC-8 analyses, we highlight the most promising signatures for $W^{'}$ discovery at the 14 TeV LHC. We find in particular very promising the study of $W^{'}$ decay modes into vector-like top partners, specifically the decay into a doublet of custodian heavy fermions, $T_{5/3} T_{2/3}$, and the decay into a heavy fermion plus a Standard Model quark. We perform a detailed parton level analysis of the channel $W^{'}\to T_{5/3} T_{2/3}$ in the same-sign dilepton final state, finding that it is a very promising signature to test the region at high $W^{'}$ mass, $m_{W^{'}}\gtrsim 2$ TeV, and of the $W^{'}\to Tb$ mode, that is one of the best channels to test the intermediate $W^{'}$ mass region and that, already with the LHC-8 data, could extend the present exclusion bounds.Comment: 25 pp. v2: minor changes, references added, version to appear in Phys. Rev.

A combinatorial solution for the current fluctuations in the exclusion process

We conjecture an exact expression for the large deviation function of the stationary state current in the partially asymmetric exclusion process with periodic boundary conditions. This expression is checked for small systems using functional Bethe Ansatz. It generalizes a previous result by Derrida and Lebowitz for the totally asymmetric exclusion process, and gives the known values for the three first cumulants of the current in the partially asymmetric model. Our result is written in terms of tree structures and provides a new example of a link between integrable models and combinatorics.Comment: 7 page

Discerning Elementary Particles

We extend the quantum-mechanical results of Muller & Saunders (2008) establishing the weak discernibility of an arbitrary number of similar fermions in finite-dimensional Hilbert-spaces in two ways: (a) from fermions to bosons for all finite-dimensional Hilbert-spaces; and (b) from finite-dimensional to infinite-dimensional Hilbert-spaces for all elementary particles. In both cases this is performed using operators whose physical significance is beyond doubt.This confutes the currently dominant view that (A) the quantum-mechanical description of similar particles conflicts with Leibniz's Principle of the Identity of Indiscernibles (PII); and that (B) the only way to save PII is by adopting some pre-Kantian metaphysical notion such as Scotusian haecceittas or Adamsian primitive thisness. We take sides with Muller & Saunders (2008) against this currently dominant view, which has been expounded and defended by, among others, Schr\"odinger, Margenau, Cortes, Dalla Chiara, Di Francia, Redhead, French, Teller, Butterfield, Mittelstaedt, Giuntini, Castellani, Krause and Huggett.Comment: Final Version. To appear in Philosophy of Science, July 200