17712450
Cosmic star formation history associated with quasar activity: An approach using the black hole-to-bulge mass correlation
The tight correlation between the masses of central black holes and their host spheroids in nearby galaxies and active galactic nuclei (AGNs) suggests that black hole growth is closely related to their spheroid formation. Based on our previous work regarding such a joint evolutionary scheme and the consequential black hole-to-bulge mass correlation, we use the X-ray luminosity function of AGN and the cosmological evolution rate, which are from ROSAT X-ray surveys, to estimate the cosmic star formation history associated with the black hole growth. By the basic assumption that the major black hole growth occurs during the luminous AGN phase, the luminosity function of AGNs as a function of redshift traces not only the accretion history of the black holes but also the cosmic star formation history of the spheroids. Although the space density of the especially luminous quasars is very low, we show that the total amount of star formation associated with the massive black hole growth is almost the same as that of Lyman break galaxies detected by the current optical deep surveys. We thus argue that the optical deep surveys may miss about half of the net star formation in our universe. This is probably due in part to significant dust extinction, as well as the small field of view of previous optical surveys, which cannot sample such rare events with relatively short timescale. However, the far-infrared emission from the dust heated by ongoing star formation during the black hole growth could sufficiently account for the observed SCUBA number counts and would be the probable dominating energy source of the SCUBA population.
145039581
Contribution of starburst mergers at z ∼ 1 to the strong evolution of infrared and submillimeter deep surveys
Recent far-infrared and submillimetre waveband observations revealed a large number of Ultraluminous Infrared Galaxies (ULIGs) with infrared luminosities >10 L . These sources are proposed to lie at redshifts above one, and in normally interacting systems with very dusty environments. We discussed in a previous paper that a population with a fast evolving infrared burst phase triggered by gas-rich mergers at z ∼ 1 predicted successfully the steep slope of faint IRAS 60 μm source counts within the flux range of 100 mJy ∼ 1 Jy, still leaving the infrared background level at this wavelength compatible with the upper limit from recent high energy TeV γ ray detection of Mrk 501. To extend the model to mid and far infrared wavelengths, we adopt a reasonable template spectral energy distribution typical for nearby-infrared-bright starburst galaxies (Lir <= 10 12 L ), such as Arp 220. We construct the SED for the dusty starburst mergers at z ∼ 1 by a simple dust extinction law and a thermal continuum assumption for the far-infrared emission. Since the radiation process at mid-infrared for these starburst merging systems is still uncertain, we assume it is similar to the MIR continuum of Arp 220, but modify it by the observed flux correlation of ULIGs from IRAS and ISOCAM deep surveys. We show in this paper that the strong evolution of the European Large Area ISO Survey (ELAIS) at 90μm, ISO 170μm and the Submillimeter deep survey at 850μm could be sufficiently accounted for by such an evolutionary scenario, especially the hump of the ISOCAM 15μm source count around 0.4 mJy. From current best fit results, we find that the dust temperature of those extremely bright starburst merging system at z ∼ 1 would be higher than that of Arp 220 for a reconciliation of the multi-wavelength infrared deep surveys. We thus propose that the infrared burst phase of dusty starburst galaxies or AGNs from gas-rich mergers at z ∼ 1 could contribute significantly to the strong evolution of the IRAS 60μm, the ISO 15μm, 90μm, 170μm, as well as the SCUBA 850μm number counts, while being compatible with the current observational limits of the cosmic infrared background and the redshift distributions. The major difference of our current model prediction is that we see a fast convergence of the differential number counts at 60μm below 50 mJy, which is about a factor of two brighter than other model predictions. Future infrared satellites like Astro-F or SIRTF would give strong constraints to the models.
17261464
Black hole to bulge mass correlation in Active Galactic Nuclei: a test for the simple unified formation scheme
A mass correlation of central black holes and their spheroids similar to 0.002 (within a factor of three) is suggested by Hubble Space Telescope (HST) and various ground-based CCD photometries of early type galaxies. The near-IR images of quasar hosts and the emission line measurements of Broad Line Region for bright QSOs present a similar correlation, which supports the speculation of an evolutionary linkage between the early active QSO phase and the central black holes in normal galaxies. On the other hand, recent reverberation mapping of a sample of Seyferts shows a broad distribution of black hole to bulge mass ratio with a mean of similar to 10(-3.5), about one magnitude lower than the value in early type galaxies and bright QSOs. Adopting a simple unified formation scheme for QSOs and Seyferts, we will discuss in this letter the dependence of the black hole to bulge mass ratio in Active Galactic Nuclei (AGNs) on the environmental parameters of the host galaxies. We show a broad distribution of the mass correlation could be due to different velocity dispersion of the accreting gas from different Formation mechanism, and the mass ratio in normal galaxies and bright QSOs is probably a limit case of black hole evolution by merger enhanced accretion close to Eddington limit.
2976540
Infrared–red cores in nearby elliptical galaxies
We present the Spitzer Space Telescope Infrared Array Camera observations for a sample of local elliptical galaxies to study later stages of active galactic nucleus (AGN) activity. A sample of 36 elliptical galaxies is selected from the Palomar spectroscopic survey. We detect nuclear non-stellar infrared emission in nine of them. There is unambiguous evidence of circumnuclear dust in these nine galaxies in their optical images. We also find a remarkable correlation between the infrared excess emission and the nuclear radio/X-ray emission, suggesting that infrared excess emission is tightly related to nuclear activity. The possible origin of infrared excess emission from hot dust heated by the central AGN is supported by the spectral indices of the infrared excess emission.
55112542
Statistical Study of Coronal Mass Ejection Source Locations: II. Role of Active Regions in CME Production
This is the second paper of the statistical study of coronal mass ejection (CME) source locations, in which the relationship between CMEs and active regions (ARs) is statistically studied on the basis of the information of CME source locations and the ARs automatically extracted from magnetic synoptic charts of Michelson Doppler Imager (MDI) during 1997 -- 1998. It is found that about 63% of the CMEs are related with ARs, at least about 53% of the ARs produced one or more CMEs, and particularly about 14% of ARs are CME-rich (3 or more CMEs were generated) during one transit across the visible disk. Several issues are then tried to clarify: whether or not the CMEs originating from ARs are distinct from others, whether or not the CME kinematics depend on AR properties, and whether or not the CME productivity depends on AR properties. The statistical results suggest that (1) there is no evident difference between AR-related and non-AR-related CMEs in terms of CME speed, acceleration and width, (2) the size, strength and complexity of ARs do little with the kinematic properties of CMEs, but have significant effects on the CME productivity, and (3) the sunspots in all the most productive ARs at least belong to $\beta\gamma$ type, whereas 90% of those in CME-less ARs are $\alpha$ or $\beta$ type only. A detailed analysis on CME-rich ARs further reveals that (1) the distribution of the waiting time of same-AR CMEs, consists of two parts with a separation at about 15 hours, which implies that the CMEs with a waiting time shorter than 15 hours are probably truly physical related, and (2) an AR tends to produce such related same-AR CMEs at a pace of 8 hours, but cannot produce two or more fast CMEs (>800 km/s) within a time interval of 15 hours. This interesting phenomenon is particularly discussed.
91211418
Further evidences for enhanced nuclear cross-sections observed in 44 GeV carbon ion interactions with copper
119215482
LOCAL LUMINOUS INFRARED GALAXIES. III. CO-EVOLUTION OF BLACK HOLE GROWTH AND STAR FORMATION ACTIVITY?*
Local luminous infrared (IR) galaxies (LIRGs) have both high star formation rates (SFR) and a high AGN (Seyfert and AGN/starburst composite) incidence. Therefore, they are ideal candidates to explore the co-evolution of black hole (BH) growth and star formation (SF) activity, not necessarily associated with major mergers. Here, we use Spitzer/IRS spectroscopy of a complete volume-limited sample of local LIRGs (distances of <78 Mpc). We estimate typical BH masses of 3 × 10 7 Musing (Neiii) 15.56 μm and optical (Oiii) λ5007 gas velocity dispersions and literature stellar velocity dispersions. We find that in a large fraction of local LIRGs, the current SFR is taking place not only in the inner nuclear ∼1.5 kpc region, as estimated from the nuclear 11.3 μm PAH luminosities, but also in the host galaxy. We next use the ratios between the SFRs and BH accretion rates (BHAR) to study whether the SF activity and BH growth are contemporaneous in local LIRGs. On average, local LIRGs have SFR to BHAR ratios higher than those of optically selected Seyferts of similar active galactic nucleus (AGN) luminosities. However, the majority of the IR-bright galaxies in the revised-Shapley-Ames Seyfert sample behave like local LIRGs. Moreover, the AGN incidence tends to be higher in local LIRGs with the lowest SFRs. All of this suggests that in local LIRGs there is a distinct IR-bright star-forming phase taking place prior to the bulk of the current BH growth (i.e., AGN phase). The latter is reflected first as a composite and then as a Seyfert, and later as a non-LIRG optically identified Seyfert nucleus with moderate SF in its host galaxy.
118651701
STRONG FIELD EFFECTS ON EMISSION LINE PROFILES: KERR BLACK HOLES AND WARPED ACCRETION DISKS
If an accretion disk around a black hole is illuminated by hard X-rays from non-thermal coronae, fluorescent iron lines will be emitted from the inner region of the accretion disk. The emission line profiles will show a variety of strong field effects, which may be used as a probe of the spin parameter of the black hole and the structure of the accretion disk. In this paper, we generalize the previous relativistic line profile models by including both the black hole spinning effects and the non-axisymmetries of warped accretion disks. Our results show different features from the conventional calculations for either a flat disk around a Kerr black hole or a warped disk around a Schwarzschild black hole by presenting, at the same time, multiple peaks, rather long red tails, and time variations of line profiles with the precession of the disk. We show disk images as seen by a distant observer, which are distorted by the strong gravity. Although we are primarily concerned with the iron K-shell lines in this paper, the calculation is general and is valid for any emission lines produced from a warped accretion disk around a black hole.
55999663
An Experimental Exploration of the QCD Phase Diagram: The Search for the Critical Point and the Onset of De-confinement
The QCD phase diagram lies at the heart of what the RHIC Physics Program is
all about. While RHIC has been operating very successfully at or close to its
maximum energy for almost a decade, it has become clear that this collider can
also be operated at lower energies down to 5 GeV without extensive upgrades. An
exploration of the full region of beam energies available at the RHIC facility
is imperative. The STAR detector, due to its large uniform acceptance and
excellent particle identification capabilities, is uniquely positioned to carry
out this program in depth and detail. The first exploratory beam energy scan
(BES) run at RHIC took place in 2010 (Run 10), since several STAR upgrades,
most importantly a full barrel Time of Flight detector, are now completed which
add new capabilities important for the interesting physics at BES energies. In
this document we discuss current proposed measurements, with estimations of the
accuracy of the measurements given an assumed event count at each beam energy.