1202.0717
Measuring bulk motion of X-ray clusters via the kinematic SZ effect: summarizing the "dark flow" evidence and its implications
Kashlinsky, Atrio-Barandela, Ebeling
(A review draft.) Present comprehensive discussion of peculiar velocity field measured recently on very large scales with a method using X-ray galaxy clusters as tracers. Measurement based on kSZ, and uses a large catalog of X-ray selected clusters and all-sky CMB maps from WMAP. Method probes the dipole of CMB temperature field evaluated at the cluster positions [? pec vel, I guess] and within the aperture in which the CMB monopole contribution vanishes, thereby isolating the signal remaining from the kSZ effect. The detection of a highly significant dipole out to the depth of at least ~800 Mpc casts doubt on the notion that gravitational instability from the observed mass distribution is the sole (or even dominant) cause of the detected motions. Rather it appears that the flow may extend across the entire observable Universe. Possible implications include the possibility to constrain the primeval preinflationary structure of space-time and landscape, and/or the need for modivications of presently known physics (arising from a higher dimensional structure of gravity). Review these possibilities in light of the measurements described here, and specifically discuss the prospects of future measurements and the issues they should resolve. We address the consistence of these large-scale velocity measurements with those obtained on smaller scales by studies using galaxies as tracers, and resolve the discrepancies with two recent claims based on modified CMB analysis schemes.
1202.0728
Symmetry and anti-symmetry of the CMB anisotropy pattern
Kim, Naselsky, Hansen
Parity of CMB data shows large-scale odd-parity preference. Investigate the association of the systematics with this anomaly, but have not found a definite non-cosmological cause. Investigate the phase of even and odd multipole data respectively, and found the behavior distinct from each other. Noting the odd-parity preference anomaly, fit a cosmo model respectively to odd and even multipole data, and found significant parametric tension. Besides anomalies explicitly associated with parity, there are anomalous lack of LS correlation in CMB data. Noting the equivalence between the power spectrum and the correlation, investigate the associating between the lack of large-angle correlation and the odd-parity preference of the angular power spectrum. From analysis, find that the odd-parity preference at low multipoles is phenomenologically identical with the lack of large-angel correlation.
1202.0761
A Herschel view of the far-IR properties of submillimeter galaxies
Magnelli, ...Albrecht, ... Bertoldi, ... Capak, .... Cooray, ... et al
Study 61 submillimeter galaxies (SMGs) selected from ground-based surveys, with known spectro-zs and observed with Herschel as part of the PACS Evolutionary Probe (PEP) and the Herschel Multi-tiered Extragalactic Survey (HerMES) key programmes. Broad far IR coverage (100-600um) from PACS and SPIRE. Use power-law T distribution model to derive IR luminosities and dust temperatures, measure dust emissivity spectral index for SMGs of beta=2.0 pm 0.2. Results unveil the diversity of the SMG population. Some SMGs exhibit extreme IR luminosityes of 1e13 Lsun and relatively warm dust components, while others are fainter (1e12 Lsun) and are biased towards cold dust temperatures. The extreme IR luminosities of some SMGs (LIR>1e12.7 Lsun,26/61 systems) imply SFRs of >500Msun/yr. Such high SFRs are difficult to reconcile with a secular mode of star formation, and may instead correspond to a merger-driven stage in the evolution of these galaxies. Another observational argument in favour of this scenario is the presence of dust temperatures warmer than that of SMGs of lower luminosities (~40K, not ~25K), consistent with observations of local ULIRGs triggered by major mergers and with results from hydrosims of major mergers combined with radiative transfer calculations. Luminous SMGs are also offset from normal SF galaxies in the stellar mass-SFR plane, suggesting that they are undergoing starburst events with short duty cycles, compatible with the major merger scenario. On the other hand, a significant fraction of the low IR luminosity SMGs have cold dust temperatures, are located close o the MS of SF, and thus might be evolving through a secular mode of SF.
* which redshift ranges are they talking about???
1202.0775
Cosmological redshift in FRW metrics with constant spacetime curvature
Melia
The interpretation of z as due to the "stretching" of space is coordinate dependent in a NFW universe with constant curvature. Namely, prove that redshift may also be calculated solely from the effects of kinematics and gravitational acceleration. Suggests that its dependence on the expansion factor is simply a manifestation of the high degree of symmetry in FRW, and ought not to be viewed as evidence in support of the idea that space itself is expanding.
1202.0780
An extended XMM-Newton observation of the Seyfert galaxy NGC 4051 - III. FeK emission and absorption
Pounds, Vaughan
Examine the Fe K spectral region in detail and find support for two distinct velocity components in the highly ionized absorber, with values corresponding to the putative fast wind (~0.12c) and the post-shock flow (v~5000-7000 km/s). Absorption line structure vary on an orbit-to-orbit timescale, apparently responding to both a short term increase in ionizing flux and to changes in the soft X-ray (and simultaneous UV) luminosity. The latter result is particularly interesting in providing independent support for the existence of shocked gas being cooled primarily by Compton scattering of accretion disc photons. The Fe K emission is represented by a narrow fluorescent line from near-neutral matter, with a weak red wing modeled by a relativistic decline. The narrow line flux is quasi-constant throughout the 45-day campaign, but is resolved, with a velocity width consistent with scattering from a componet of the post-shock flow. Evidence for a P Cygni profile is seen in several individual orbit spectra for resonance transitions in both Fe XXV and Fe XXVI.
* Seyfert Galaxy: class of galaxies with nuclei that produce spectral line emission from highly ionized gas. A subclass of AGN, with SMBH of 1e7-8 Msun. Bright emission lines of H, He, N and O with strong Doppler broadening (500 to 4000 km/s). Also show strong emission in the IR, UV, and X-ray, but only 5% are radio loud. Radio emission believed to be from synchrotron emission from the jet; IR from radiation in other bands reprocessed by dust near the nucleus; highest energy photons from inverse compton scattering by a high T corona near the BH. Type 1: Broad and narrow emission lines; Type 2: only narrow lines.
* Reverberation mapping: use short timescale variability in the broad line region to try to determine the location and morphology of the emitting region.
1202.0791
Beyond Strömgren spheres and wind-blown bubbles: an observational perspective on H II region feedback
Povich
* Strömgren sphere: a sphere of H II around a young star of the spectral classes O or B. The theory was derived by Strömgren in 1937. The Rosette Nebula is the most prominent example of this type of emission nebula from the H II regions.
30 Doradus, the most luminous HII region in the Local Group. Search for bubble shaped structures.
1202.0804
Compact object coalescence rate estimation from short gamma-ray burst observation
Petrillo, Dietz
* short GRB: coalescence of compact objects, like NSs and BHs.
From 15 short gamma-ray bursts, a range for the merger rate of 75 to 660 /Gpc^3/yr with a median rate of 180 estimated. In general agreement with similar investigations.
1202.0808
Practical methods for continuous gravitational wave detection using Pulsar Timing data
Ellis, Jenet, McLaughlin
* pulsar timing array: a set of millisecond pulsars that can be used to detect and analyse gravitational waves. Such a detection would result from a detailed investigation of the arrival times of pulses emitted by these millisecond pulsars (not prone to starquakes and accretion events). Grav waves cause the time of arrival of the pulses to vary by a few tens of nanoseconds over their wavelength. The experiments use collections of 20 to 50 pulsars to account for dispersion effects in the atmosphere and in the space between us and the pulsar. Necessary to monitor once a week; higher cadence will make it possible to detect higher-frequency gravitational waves.
Pulsar timing arrays (PTAs) posed to detect low frequence (1e-9 to 1e-7 Hz) GWs in the near future. Detection of stochastic GW BGs from SMBH binaries, studies show that single continuous sources standing out above the BG may be detectable by PTAs operating at a sensistivity sufficient to detect the stochastic BG. SMBH binaries most likely detected for PTAs. ...
1202.0819
Laser frequency comb techniques for precise astronomical spectroscopy
Murphy, Locke, Light, Luiten, Lawrence
Laser frequency combs: provide highly precise wavelength calibration for astronomical spectrographs. Show that they can also be used to measure IPS (intra-pizel sensitivity) variations in astronomical CCDs in situ. Successfully tested a laser requence comb system on the Ultra-high resolution facility spectrograph at the AAT. By modelling the 2d comb signal recorded in a single CCD exposure, find that the average IPS deviates by <8% if it is assumed to vary symmetrically about the pixel centre. Also demonstrate that series of comb exposures with absolutely known offsets between them can yield tighter constraints on symmetric IPS variations from ~100 pixels. Discuss measurement of asymmetric IPS variations and absolute wavelength calibration of astronomical spectrographs and CCDs using frequency combs.
1202.0824
Measurement of the Mass and stellar population distribution in M82 with the LBT
Greco, Martini, Thompson
Present K-band spectroscopic study of the stellar and gas kimenatics, mass distribution, and stellar populations of the archetypical starburst M82. Rotation curve out to 4kpc radius with CO stellar absorption. HI and CO emission from ISM suggest nearly Keplerian gas dynamics (implying a truncation of M82's DM halo), this data show that rotation curve is in fact flat on 1-4 kpc scales. Kinematics of Br(gamma), H2 and He I emission consistent with (but slightly higher velocities than) stellar kinematics. Estimate total dynamical mass is 1e10 Msun. Measure the equivalent width of CO as a function of distance from center of gal, investigate spatial extent of the red supergiant population. The variaton in W with radius cearly shows that RSGs dominate the light inside the 500 pc radius. M82s famous superwind is likely launched from this region, where the enclosed mass is estimated at <2e9 Msun.
1202.0827
The Hubble WFC3 test of surfaces in the outer solar system: the compositional classes of the Kuiper Belt
Fraser, Brown
* Centaurs: class of minor planets between Jupiter and Neptune. Behave with characteristics of both asteroids and comets.
First results of H/WTSOSS: purpose is to measure te surface properties of a large number of Kuiper belt objects and attempt to infer compositional and dynamical correlations. Find that the Centaurs and the low-perihelion scattered disk and resonant objects exhibit virtually identical bifurcated optical colour distributions and make up two well defined groups of object. Both groups have highly correlated optical and NIR colours which are well described by a pair of 2 component mixture models that have different red components, but share a common neutral component. The small, H606>5.6 high-perihelion excited objects are entirely consistent with being drawn from the 2 branches of the mixing model suggesting that the colour bifurcation of the Centaurs is apparent in all small excited objects. On the other hand, objects larger than H606~5.6 are not consistent with the mixing model, suggesting some evolutionary process avoided by the smaller objects. The existence of a bifurcation amongst all excited populations argues that the two separate classes of object existed in the primordial disk before the excited Kuiper belt was populated. The cold classical objects exhibit a different type of surface which has colours that are consistent with being drawn from the red branch of the mixing model, but with much higher albedos.
1202.0882
A super-damped Lyman-alpha QSO absorber at z=2.2
Kulkarni, Meiring, Som, Peroux, York, Khare, Lauroesch
Discovery of a "super-damped" Lya absorber at z_abs=2.2 twoard QSO in SDSS, followed up with VLT UVES spectroscopy, with log(N_HI)=22, the second highest. Element abundances for Si, Zn, Cr, Hi, Fe, Ti, P, Cu. Detection of Lya emission in the DLS trough, implying a SFR of 10 M_sun/yr in the absence of dust attenuation. C II absorption also detected, SFR surface density derived (1e-2 Msun/yr/kpc^2). Estimate electron density in the range 3.5e-4 to 24 cm^-3 fromr CI, and 0.5-0.9 cm^-3 from Si II. Overall, this is a robustly star forming, moderately enriched absorber, but with relatively low dust depletion. Low reddening for MW, LMC or SMC extinction curves [?]. No CO absorption detected, and C I absorption weak. The low dust and molecular content, reminiscent of some SMC slight-lines, may result from the lower metallicity, and a stronger radiation field (due to higher SFR). FInally, compare this absorber with other QSO and GRB DLAs.
1202.0892
Testing modified gravity models with recent cosmological observations
Zhang, Ceng, Huang, Li, Li, Li, Wang
Explore MG models using recent cosmo obs data, including SNLS3 SNIa, WMAP7 CMB, BAO SDSS DR7, and WFC3 H0 measurements. Consider DGP model, two f(R) models, and two f(T) models. Find: compared to LCDM model, MG models can not lead to an appreciable reduction of the chisq-min. The analysis of AIC and BIC shows that the simplest cosmo constant model LCDM is still more preferred by the current data, and the DGP model is strongly disfavored. In addition, also reconstruct the evolutions of the growth factor in these models. Find current available growth factor data are not enough to distinguish MG models from the LCDM model.
1202.0903
One or more bound planets per MW star from microlensing observations
Cassan, ... Wambsganss, ... Cole, et al
Exoplanets discovered using radial velocity or transit methods: show 17-30% of solar-like stars host a planet. Gravitational microlensing probes planets that are further away from their stars. A population of planets that are unbound or very far from their stars discovered by microlensing; these planets are at least as numerous as the stars in the MW. Report a statistical analysis of microlensing data that reveals the fraction of bound planets 0.5-1.0 AU from their stars. Find that 17% of stars host Jupiter-mass plaets; Cool Neptunes (10-30 M_earth), and super-Earths (5-10 M_earth) are more common; their respective abundances per star are 52% and 62%. Conclude that stars are orbited by planets as a rule, rather than the exception.
1202.0971
Size and velocity-dispersion evolution of early-type galaxies in a LCDM universe
Nipoti, Treu, Leauthaud, Bundy, Newman, Auger
ETGs are observed to be more compact at z>2 than in the local universe. Remarkably, much of this size evolution appears to take place in a short ~1.8Gyr timespan between z~2.2 and 1.3, which poses a serious challenge to hierarchical galaxy formation models where mergers occurring on similar timescale are the main mechanism for galaxy growth. Compute the merger-driven redshift evolution of stellar mass M_star propto (1+z)^aM, half mass radius Re propto (1+z)^aR, and velocity dispersion sigma0 propto (1+z)^asigma predicted by LCDM for a typical massive ETG in the redshift range z=1.3-2.2 [from simulations?]. Neglecting dissipative processes, and thus maximizing evolution in surface density, find value range for each exponent. Furthermore, find that the scatter introduced in the size-mass correlation by the predicted merger-driven growth [based on sims?] is difficult to reconcile with the tightness of the observed scaling law. Conclude that (barring unknown systematics or selection biases in the current measurements) minor and major mergers with spheroids are not sufficienet to explain the observed size growth of ETGs within the standard model.
1202.0997
PACS-Herschel FIR detections of Lya emitters at 2<z<3.5
Oteo, Bongiovanni, ... Genzel, et al
Analyze physical properties of a sample of 56 spectro selected SF Lya emitting galaxies at 2<z<3.5 using SED fitting procedure from rest-frame UV to mid-IR and direct 160 um observations from PACS on Herschel. Define LAEs as those LYa emitting galaxies whose rest-frame Lya equivalent widths are >20A, the typical threshold in narrow-band searches. Lya emitting galaxies with Lya EW are called non-LAEs. As a result of an individual SED fitting for each object, find that the studied sample of LAEs contains galaxies with ages mostly below 100 Myr and a wide variety of dust attenuations, SFRs, and stellar masses. The heterogeneity in the physical properties is also seen in the morphology, ranging from bulge-like galaxies to highly clumpy systems. In this way, find LAEs at 2<z<3.5 are very diverse, and do not have a bimodal nature, as suggested in previous works. Furthermore, the main differences between LAEs and non-LAEs is their dust attenuation, because LAEs are not as dusty as non-LAEs. On the FIR side, four galaxies of the sample (two LAEs and two non-LAEs) have PACS-FIR counterparts. Their total IR luminosity place all of them in the ULIRG regime and are all dusty objects, with A>4 mag. This is an indication from direct FIR measurements that dust and lya emission are not mutually exclusive. This population of red and dusty LAEs is not seen at z~0.3, suggesting an evolution with redshift of the IR nature of galaxies selected via their Lya emission.
1202.1020
Testing galactic magnetic field models using near-infrared polarimetry
Pavel, Clemens, Pnnick
Combine NIR starlight linear polarimetry with simulated observations to constrain dynamo models of the galactic magnetic field. Total of 10k stars photometrically measured, and 1k had usable polarizations. Observed distribution of polarization position angles with Galactic latitude and cumulative distribution function of the measured polarization are compared to predicted values. Prediction lack the effects of turbulence (idealized); comparison allows significant rejection of A0-type magnetic field models [what are they?]. S0 and disk-even halo-odd magnetic field geometries are also rejected, but at lower significance. New predictions of spiral-type, axisymmetric magnetic fields, when combined with new NIR observations, constrain the Galactic magnetic field spiral pitch angle to -6 pm 2 deg.
1202.1023
Characterization of turbulence from submillimeter dust emission
Chitsazzadeh, Houde, Hildebrand, Vaillancourt
* Stokes parameters: set of values that describe the polarization state of EM radiation. Stokes vector spans the space of unpolarized, partially polarized, and fully polarized light.
Use recent technique for estimating the turbulent component of magnetic field to derive the structure functions of the unpolarized emission as well as the Stokes Q and U parameters of the polarized emission. SHARP polarization data allow determination of turbulent correlation scales. The estimated values for these length scales are ~20 mpc at 450 pc, the distance to OMC-1. Current results consistent with previous results obtained through other methods, and may indicate presence of anisotropy in magnetized turbulence. Infer a weak coupling between the dust component responsible for the unpolarized emission N and the magnetic field B from the significant difference between their turbulent correlation length scales.
1202.1026
Practices in Code discoverability
Teuben, Allen, Nemiroff, Shamir
Some codes in astrophysics are public, some are not. Why not? Implement a code sharing system.
1202.1028
Practices in Code discoverability: astrophysics source code library (ASCL)
1202.1026
Practices in Code discoverability
Teuben, Allen, Nemiroff, Shamir
Some codes in astrophysics are public, some are not. Why not? Implement a code sharing system.
1202.1028
Practices in Code discoverability: astrophysics source code library (ASCL)
Allen, Teuben, Nemiroff, Shamir
Describe ASCL, active approach to sharing astrophysical source code. Scrounge from archive (coder does not have to actively submit). Already has 340 codes, average of 19 codes/mo added. Benefits and future plans discussed.
1202.1034
Spectral components analysis of diffuse emission processes
Malyshev
Develop method to separate the components of a diffuse emission process based on an association with the energy spectra. Most of the existing methods use some information about the spatial distribution of components, e.g., closeness to an external template, independence of components etc., in order to separate them. Propose a method where one puts conditions on the spectra only. Advantages: (1) it's internal, the maps of the components are constructed as combinations of data in different energy bins (2) components may be correlated among each other, (3) is semi-blind. Derive CMB map and the foreground maps for 7 years of WMAP data. In Appendix, present a generalization of the method, where one can also add a number of external templates.
1202.1035
Water formation through a quantum tunneling surface reaction, OH + H2, at 10K
Oba, Watanabe, Hama, Kuwahata, Hidaka, Kouchi
Experimentally demonstrate that solid H2O is formed through the surface reaction OH + H2 at 10K; first experimental evidence. Find OH+H2 is ~10x more efficient than HDO formation through the reaction OH + D2. The isotope effect results in the differences in the effective mass of each reaction, indicating that the reactions proceed through quantum tunneling.
1202.1044
Kinematics and excitation of the ram pressure stripped ionized gas filaments in the coma cluster of galaxies
Yoshida, Yagi, Komiyama, Furusawa, Kashikawa, Hattori, Okamura
Present results of deep imaging and spectroscopic observations of very extended ionized gas (EIG) around four member galaxies of the Coma cluster of galaxies. The EIGs were serendipitously found in an H-alpha narrow band imaging survey of the central region of the Coma cluster. The relative radial velocities of the EIGs wrt the systemic velocities of the parent galaxies from which they emanate increase almost monotonically with the distance from the nucleus of the respective galaxies, reaching -400 to -800 km/s at around 40-80 kpc from the galaxies. The one-sided morphologies and the velocity fields of the EIGs are consistent with the predictions of numerical simulations of ram pressure stripping. Find a very low-velocity filament (v_rel = -1300 km/s) at the SE edge of the disk of IC5050. Some bright compact knots in the EIGs of RB199 and IC4040 exhibit blue continuum and strong Ha emission. The EWs of the Ha emission exceed 200A, and are greater than 1000A for some knots. The emission line intensity rations of the knots are basically consistent with those of sub-solar abundance H II regions. These facts indicate that intensive SF occurs in the knots. Some filaments, including the low velocity filament of the IC4040 EIG, exhibit shock-like emission line spectra, suggesting that shock heating plays an important role in ionization and excitation of the EIGs.
1202.1064
Extreme coronal line emitters: tidal disruption of stars by massive BHs in galactic Nuclei?
Wang, Zhou, Komossa, Wang, Yuan, Yang
Evidence for tidal disruption of stars seen in SDSS spectra: Extremely strong coronal lines from Fe X to Fe XIV in a sample of 7 galaxies. Galaxies are non-active (evidenced by narrow-line ratios) show broad emission lines of complex profiles in more than half of the sample. Both the high ionization coronal lines and the broad lines turn out to be fading on time scales of years in objects observed with spectro follow-ups, suggesting their transient nature. Variations of inferred non-stellar continua, which have absolute magnitudes of at least -16 to -18 mag in the g-band are also detected in more than half of the sample. The coronal line emitters reside in sub-L* disk galaxies with small stellar velocity dispersions. The sample seems to form two distinct types based on the presence or absence of the Fe VII lines, with the latter having relatively low luminosities of O III , Fe XI and the host galaxies. These characteristics can most naturally be understood in the context of transient accretion onto intermediate mass BGs at galactic centers following tidal disruption of stars in a gas rich environment. Estimate the indicence of such events to be around 1e-5 / year for galaxy with -21<M_i<-18.5.
1202.1086
The orbit of 2010 TK7. Possible regions of stability for other Earth Trojan asteroids
Dvorak, Lhotka, Zhou
First Earth Trojan observed near L4. (a) Restricted 3-body problem. (b) use precise numerical methods to integrate the orbit forward adn backward in time in different dynamical models. Calculate probability of capture and escape. (c) Perform an extensive numerical investigation of the stability region of the Earth's Lagrangian points. Present a detailed parameter study in the regime of possible stable tadpole and horseshoe orbits of additional Earth-Trojans, i.e., with respect to the semi-major axes and inclinations of thousands of fictitious Trojans. All 3 approaches underline that the Earth Trojan asteroid 2010 TK7 finds himself in an unstable region on the edge of a stable zone; additional Earth-Trojan asteroids may be found in this regime of stability.
1202.1138
A universal stellar-mass and size relation of galaxies in GOODS-N region
Ichikawa, Kajisawa, Akhlaghi
Present scaling relation between stellar-mass (Mstar) and the size of galaxies at 0.3<z<3 for half-(R_50) and 90 percent-light (R_90) radii, using a deep K-band selected catalogue taken with the Subaru MORICS in the GOODS-N region. The logarithmic slope R propto Mstar^0.1-0.2 is independent of redshift in a wide mass range of Mstar ~ 1e8-11 Msun, irrespective of galaxy populations (SF, quiescent). The offset change is <50 percent. Provided that optical light in the rest frame traces the stellar mass of galaxies, the universal relation demonstrates that the stellar mass was build up in galaxies over their cosmic histories in a similar manner on average irrelevant to galaxy mass. The small offset in each stellar mass bin from the universal relation shows weak size evolution at a given mass. There is a moderate increase of 30-50 percent for R_50 and R_90 for less massive galaxies (Mstar 1e11 Msun) the evolution if 70-80% increase in R_90 from z~3 to 0.3, though that in R_50 is weaker. The evolution of compactness factor, R_50/R_90, which becomes smaller at lower redshift, is suggestive of minor merging effect in the outer envelope of massive galaxies.
1202.1182
Anatomy of helical relativistic jets: the case of S5 0836+710
Perucho, Kovalev, Lobanov, Hardee, Agudo
Helical structures are common in extragalactic jets. They are usually attributed in the literature to periodical phenomena in the source (precession). From VLBI data on the above quasar, hypothesize that the ridge-line of helical jets corresponds to a pressure maximum in the jet and assume that the helically twisted pressure maximum is the result of a helical wave pattern. This interpretation allows explaining jet misalignment between parsec and kpc scales when the viewing angle is small, and also shows that high-frequency observations may show only a small region of the jet flow concentrated around the maximum pressure ridge-line observed at low frequencies. Work provides a potential explanation for the apparent transversal superluminal speeds observed in several extragalactic jets by means of transversal shift of an apparent core position with time.
1202.1196
Evolution of intrinsic ellipticity correlations due to peculiar motion
Giahi-Saravani, Schaefer
Time-evolution of intrinsic correlations of galaxy ellipticities due to peculiar motion. Model: galaxy ellipticities are determined from the angular momentum of their host haloes, which can be computed from the fluctuations of Gaussian fields. Subsequent peculiar motion distorts the ellipticity field and causes changes in the ellipticity correlations. Using analogies between this problem of shifted ellipticity tensors and displacement of polarization tensors in gravitational lensing of the CMB compute E and B mode spectra of the time-evolved ellipticity field, where the displacements are modelled with first and second order Lagrangian perturbation theory. For EUCLID, ellipticity correlations are decreased on large multipoles l>1000, amounting to up to 10% in the E-mod spectrum and up to 50% in the B-mode spectrum at l~3000 due to the dispersing effect of peculiar motion. E/B-mode conversion in analogy to CMB-lensing is present but small. Conclude that distortions of the ellipticity field due to peculiar motion is not affecting the prediction of ellipticity models on the scales relevant for lensing in the case of EUCLID's galaxy distribution, but should affect larger scales for surveys at lower redshifts.
1202.1225
The long gamma-ray burst rate and the correlation with host galaxy properties
Elliott, Greiner, Khochfar, Schady, Johnson, Rau
Epoch of reionization: periods of galaxy mergers and properties of other cosmo encounters, the cosmic SFH, is of fundamental importance. Using LGRBs (associating them with the death of massive stars), the CSFH can be probed to higher redshift thant current conventional methods. No consensus has been reached on the manner in which the LGRB rate traces the CSFH, leaving questions mentioned mostly unexplored by this method. Observations by the GRB NIR detector has acquired highly complete LGRB samples. Driven by these completeness levels and new evidence of LGRBs occurring in more massive and metal rich galaxies than previously thought, the possible biases of the LGRBR-CSFH connectio nare investiigated over a large range of aglaxy properties. THe CSFH is modelled using empirical fits o the galaxy mass function and galaxy SFRs. Biasing the CSFH by metallicity cuts, mass range boundaries, and other unknown redshift dependencies, a LGRBR is generated and compared to the highly complete GROND sample. Find: no strong preferecne for a metallicity cut or fixed galaxy mass boundaries and that there are no unknown redshift effects, in contrast to previous work which suggest values of Z/Z_sun~0.1-0.3. From the best-fit models, predict that 1.2% of the LGRB burst sample exists above z=6. The linear relationship between the LGRBR and the CSFH suggested by the resutls implies that redshift biases present in previous LGRB samples significantly affect the inferred dependencies of LGRBs on their host galaxy properties. Such biases can lead to an interpretation of metallicity limitations and evolving LGRB luminosity functions.
Describe ASCL, active approach to sharing astrophysical source code. Scrounge from archive (coder does not have to actively submit). Already has 340 codes, average of 19 codes/mo added. Benefits and future plans discussed.
1202.1034
Spectral components analysis of diffuse emission processes
Malyshev
Develop method to separate the components of a diffuse emission process based on an association with the energy spectra. Most of the existing methods use some information about the spatial distribution of components, e.g., closeness to an external template, independence of components etc., in order to separate them. Propose a method where one puts conditions on the spectra only. Advantages: (1) it's internal, the maps of the components are constructed as combinations of data in different energy bins (2) components may be correlated among each other, (3) is semi-blind. Derive CMB map and the foreground maps for 7 years of WMAP data. In Appendix, present a generalization of the method, where one can also add a number of external templates.
1202.1035
Water formation through a quantum tunneling surface reaction, OH + H2, at 10K
Oba, Watanabe, Hama, Kuwahata, Hidaka, Kouchi
Experimentally demonstrate that solid H2O is formed through the surface reaction OH + H2 at 10K; first experimental evidence. Find OH+H2 is ~10x more efficient than HDO formation through the reaction OH + D2. The isotope effect results in the differences in the effective mass of each reaction, indicating that the reactions proceed through quantum tunneling.
1202.1044
Kinematics and excitation of the ram pressure stripped ionized gas filaments in the coma cluster of galaxies
Yoshida, Yagi, Komiyama, Furusawa, Kashikawa, Hattori, Okamura
Present results of deep imaging and spectroscopic observations of very extended ionized gas (EIG) around four member galaxies of the Coma cluster of galaxies. The EIGs were serendipitously found in an H-alpha narrow band imaging survey of the central region of the Coma cluster. The relative radial velocities of the EIGs wrt the systemic velocities of the parent galaxies from which they emanate increase almost monotonically with the distance from the nucleus of the respective galaxies, reaching -400 to -800 km/s at around 40-80 kpc from the galaxies. The one-sided morphologies and the velocity fields of the EIGs are consistent with the predictions of numerical simulations of ram pressure stripping. Find a very low-velocity filament (v_rel = -1300 km/s) at the SE edge of the disk of IC5050. Some bright compact knots in the EIGs of RB199 and IC4040 exhibit blue continuum and strong Ha emission. The EWs of the Ha emission exceed 200A, and are greater than 1000A for some knots. The emission line intensity rations of the knots are basically consistent with those of sub-solar abundance H II regions. These facts indicate that intensive SF occurs in the knots. Some filaments, including the low velocity filament of the IC4040 EIG, exhibit shock-like emission line spectra, suggesting that shock heating plays an important role in ionization and excitation of the EIGs.
1202.1064
Extreme coronal line emitters: tidal disruption of stars by massive BHs in galactic Nuclei?
Wang, Zhou, Komossa, Wang, Yuan, Yang
Evidence for tidal disruption of stars seen in SDSS spectra: Extremely strong coronal lines from Fe X to Fe XIV in a sample of 7 galaxies. Galaxies are non-active (evidenced by narrow-line ratios) show broad emission lines of complex profiles in more than half of the sample. Both the high ionization coronal lines and the broad lines turn out to be fading on time scales of years in objects observed with spectro follow-ups, suggesting their transient nature. Variations of inferred non-stellar continua, which have absolute magnitudes of at least -16 to -18 mag in the g-band are also detected in more than half of the sample. The coronal line emitters reside in sub-L* disk galaxies with small stellar velocity dispersions. The sample seems to form two distinct types based on the presence or absence of the Fe VII lines, with the latter having relatively low luminosities of O III , Fe XI and the host galaxies. These characteristics can most naturally be understood in the context of transient accretion onto intermediate mass BGs at galactic centers following tidal disruption of stars in a gas rich environment. Estimate the indicence of such events to be around 1e-5 / year for galaxy with -21<M_i<-18.5.
1202.1086
The orbit of 2010 TK7. Possible regions of stability for other Earth Trojan asteroids
Dvorak, Lhotka, Zhou
First Earth Trojan observed near L4. (a) Restricted 3-body problem. (b) use precise numerical methods to integrate the orbit forward adn backward in time in different dynamical models. Calculate probability of capture and escape. (c) Perform an extensive numerical investigation of the stability region of the Earth's Lagrangian points. Present a detailed parameter study in the regime of possible stable tadpole and horseshoe orbits of additional Earth-Trojans, i.e., with respect to the semi-major axes and inclinations of thousands of fictitious Trojans. All 3 approaches underline that the Earth Trojan asteroid 2010 TK7 finds himself in an unstable region on the edge of a stable zone; additional Earth-Trojan asteroids may be found in this regime of stability.
1202.1138
A universal stellar-mass and size relation of galaxies in GOODS-N region
Ichikawa, Kajisawa, Akhlaghi
Present scaling relation between stellar-mass (Mstar) and the size of galaxies at 0.3<z<3 for half-(R_50) and 90 percent-light (R_90) radii, using a deep K-band selected catalogue taken with the Subaru MORICS in the GOODS-N region. The logarithmic slope R propto Mstar^0.1-0.2 is independent of redshift in a wide mass range of Mstar ~ 1e8-11 Msun, irrespective of galaxy populations (SF, quiescent). The offset change is <50 percent. Provided that optical light in the rest frame traces the stellar mass of galaxies, the universal relation demonstrates that the stellar mass was build up in galaxies over their cosmic histories in a similar manner on average irrelevant to galaxy mass. The small offset in each stellar mass bin from the universal relation shows weak size evolution at a given mass. There is a moderate increase of 30-50 percent for R_50 and R_90 for less massive galaxies (Mstar 1e11 Msun) the evolution if 70-80% increase in R_90 from z~3 to 0.3, though that in R_50 is weaker. The evolution of compactness factor, R_50/R_90, which becomes smaller at lower redshift, is suggestive of minor merging effect in the outer envelope of massive galaxies.
1202.1182
Anatomy of helical relativistic jets: the case of S5 0836+710
Perucho, Kovalev, Lobanov, Hardee, Agudo
Helical structures are common in extragalactic jets. They are usually attributed in the literature to periodical phenomena in the source (precession). From VLBI data on the above quasar, hypothesize that the ridge-line of helical jets corresponds to a pressure maximum in the jet and assume that the helically twisted pressure maximum is the result of a helical wave pattern. This interpretation allows explaining jet misalignment between parsec and kpc scales when the viewing angle is small, and also shows that high-frequency observations may show only a small region of the jet flow concentrated around the maximum pressure ridge-line observed at low frequencies. Work provides a potential explanation for the apparent transversal superluminal speeds observed in several extragalactic jets by means of transversal shift of an apparent core position with time.
1202.1196
Evolution of intrinsic ellipticity correlations due to peculiar motion
Giahi-Saravani, Schaefer
Time-evolution of intrinsic correlations of galaxy ellipticities due to peculiar motion. Model: galaxy ellipticities are determined from the angular momentum of their host haloes, which can be computed from the fluctuations of Gaussian fields. Subsequent peculiar motion distorts the ellipticity field and causes changes in the ellipticity correlations. Using analogies between this problem of shifted ellipticity tensors and displacement of polarization tensors in gravitational lensing of the CMB compute E and B mode spectra of the time-evolved ellipticity field, where the displacements are modelled with first and second order Lagrangian perturbation theory. For EUCLID, ellipticity correlations are decreased on large multipoles l>1000, amounting to up to 10% in the E-mod spectrum and up to 50% in the B-mode spectrum at l~3000 due to the dispersing effect of peculiar motion. E/B-mode conversion in analogy to CMB-lensing is present but small. Conclude that distortions of the ellipticity field due to peculiar motion is not affecting the prediction of ellipticity models on the scales relevant for lensing in the case of EUCLID's galaxy distribution, but should affect larger scales for surveys at lower redshifts.
1202.1225
The long gamma-ray burst rate and the correlation with host galaxy properties
Elliott, Greiner, Khochfar, Schady, Johnson, Rau
Epoch of reionization: periods of galaxy mergers and properties of other cosmo encounters, the cosmic SFH, is of fundamental importance. Using LGRBs (associating them with the death of massive stars), the CSFH can be probed to higher redshift thant current conventional methods. No consensus has been reached on the manner in which the LGRB rate traces the CSFH, leaving questions mentioned mostly unexplored by this method. Observations by the GRB NIR detector has acquired highly complete LGRB samples. Driven by these completeness levels and new evidence of LGRBs occurring in more massive and metal rich galaxies than previously thought, the possible biases of the LGRBR-CSFH connectio nare investiigated over a large range of aglaxy properties. THe CSFH is modelled using empirical fits o the galaxy mass function and galaxy SFRs. Biasing the CSFH by metallicity cuts, mass range boundaries, and other unknown redshift dependencies, a LGRBR is generated and compared to the highly complete GROND sample. Find: no strong preferecne for a metallicity cut or fixed galaxy mass boundaries and that there are no unknown redshift effects, in contrast to previous work which suggest values of Z/Z_sun~0.1-0.3. From the best-fit models, predict that 1.2% of the LGRB burst sample exists above z=6. The linear relationship between the LGRBR and the CSFH suggested by the resutls implies that redshift biases present in previous LGRB samples significantly affect the inferred dependencies of LGRBs on their host galaxy properties. Such biases can lead to an interpretation of metallicity limitations and evolving LGRB luminosity functions.
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