Latest in astro-ph.ga

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Massive, wide binaries as tracers of massive star formationFeb 13 2018Massive stars can be found in wide (hundreds to thousands AU) binaries with other massive stars. We use $N$-body simulations to show that any bound cluster should always have approximately one massive wide binary: one will probably form if none are present ... More
Dark-ages Reionization and Galaxy Formation Simulation - XIV. Gas accretion, cooling and star formation in dwarf galaxies at high redshiftFeb 12 2018We study dwarf galaxy formation at high redshift ($z\ge5$) using a suite of high-resolution, cosmological hydrodynamic simulations and a semi-analytic model (SAM). We focus on gas accretion, cooling and star formation in this work by isolating the relevant ... More
Dispersion of velocity gradients: Mapping magnetization with the Velocity Gradient TechniqueFeb 08 2018Recent developments of the Velocity Gradient Technique (VGT) show that the velocity provides a robust measure of magnetic field direction. In this paper, we use velocity centroids as the measures of velocity and propose a new way of studying media magnetization. ... More
The ALMA-PILS survey: The sulphur connection between protostars and comets: IRAS 16293-2422 B and 67P/Churyumov-GerasimenkoFeb 08 2018The evolutionary past of our Solar System can be pieced together by comparing analogous low-mass protostars with remnants of our Protosolar Nebula - comets. Sulphur-bearing molecules may be unique tracers of the joint evolution of the volatile and refractory ... More
The GALAH Survey Sees Stellar Streams: Dependence of Nearby Velocity Distributions on Galactic Longitude and MetallicityFeb 08 2018Using GALAH survey data of nearby stars, we look at how structure in the planar ($u,v$) velocity distribution depends on metallicity and on viewing direction within the Galaxy. In nearby stars with distance $d \lesssim 1$ kpc, the Hercules stream is most ... More
Nitrogen isotope fractionation in protoplanetary disksFeb 08 2018Aims: The two stable isotopes of nitrogen, 14N and 15N, exhibit a range of abundance ratios both inside and outside the solar system. The elemental ratio in the solar neighborhood is 440. Recent ALMA observations showed HCN/HC15N ratios from 83 to 156 ... More
A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE).I. Introduction to the SurveyFeb 08 2018The Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE) is a blind narrow-band Halpha+[NII] imaging survey carried out with MegaCam at the Canada-France-Hawaii Telescope. The survey covers the whole Virgo cluster region from its core to ... More
Chemical evolution with rotating massive star yields: I. The solar neighbourhood and the s-process elementsFeb 08 2018We present a comprehensive study of the abundance evolution of the elements from H to U in the Milky Way halo and local disk. We use a consistent chemical evolution model, metallicity dependent isotopic yields from low and intermediate mass stars and ... More
The Infrared Medium-deep Survey. IV. Low Eddington Ratio of A Faint Quasar at $z\sim6$: Not Every Supermassive Black Hole is Growing Fast in the Early UniverseFeb 08 2018To date, most of the luminous quasars known at $z\sim6$ have been found to be in maximal accretion with the Eddington ratios, $\lambda_{\rm{Edd}}\sim1$, suggesting enhanced nuclear activities in the early universe. However, this may not be the whole picture ... More
Is the Spiral Galaxy a Cosmic Hurricane?Feb 08 2018It is discussed that the formation of the spiral galaxies is drived by the cosmos background rotation, not a result of an isolated evolution proposed by the density wave theory. To analyze the motions of the galaxies, a simple double particle galaxy model ... More
Action-based dynamical models of dwarf spheroidal galaxies: application to FornaxFeb 07 2018We present new dynamical models of dwarf spheroidal galaxies (dSphs) in which both the stellar component and the dark halo are described by analytic distribution functions that depend on the action integrals. In their most general form these distribution ... More
Fast estimation of orbital parameters in Milky-Way-like potentialsFeb 07 2018Orbital parameters, such as the eccentricity and maximum vertical excursion, of stars in the Milky Way are an important tool for understanding its dynamics and evolution, but the calculation of such parameters usually relies on computationally-expensive ... More
Climbing to the top of the galactic mass ladder: evidence for frequent prolate-like rotation among the most massive galaxiesFeb 07 2018We present the stellar velocity maps of 25 massive galaxies located in dense environments observed with MUSE. Galaxies are selected to be brighter than M_K=-25.7 magnitude, reside in the core of the Shapley Super Cluster or be the brightest galaxy in ... More
Unlocking CO Depletion in Protoplanetary Disks I. The Warm Molecular LayerFeb 07 2018CO is commonly used as a tracer of the total gas mass in both the interstellar medium and in protoplanetary disks. Recently there has been much debate about the utility of CO as a mass tracer in disks. Observations of CO in protoplanetary disks reveal ... More
A Universal Entropy Profile for the Hot Atmospheres of Galaxies and Clusters within $R_{2500}$Feb 07 2018We present atmospheric gas entropy profiles for 40 early type galaxies and 110 clusters spanning several decades of halo mass, atmospheric gas mass, radio jet power, and galaxy type. We show that within $\sim 0.1R_{2500}$ the entropy profiles of low-mass ... More
Panchromatic SED modelling of spatially-resolved galaxiesFeb 07 2018We test the efficacy of the energy-balance spectral energy distribution (SED) fitting code Magphys for recovering the spatially-resolved properties of a simulated isolated disc galaxy, for which it was not designed. We perform 226,950 Magphys SED fits ... More
The dragonfly nearby galaxies survey. Iv. A giant stellar disk in ngc 2841Feb 07 2018Neutral gas is commonly believed to dominate over stars in the outskirts of galaxies, and investigations of the disk-halo interface are generally considered to be in the domain of radio astronomy. This may simply be a consequence of the fact that deep ... More
The Planes of Satellite Galaxies Problem, Suggested Solutions, and Open QuestionsFeb 07 2018Satellite galaxies of the Milky Way and of the Andromeda galaxy have been found to preferentially align in significantly flattened planes of satellite galaxies, and available velocity measurements are indicative of a preference of satellites in those ... More
Self-consistent redshift estimation using correlation functions without a spectroscopic reference sampleFeb 07 2018We present a new method to estimate redshift distributions and galaxy-dark matter bias model parameters (gdmbm) using correlation functions in a fully data driven manner. Unlike other machine learning, template methods, or correlation redshift methods, ... More
xGASS: Total cold gas scaling relations and molecular-to-atomic gas ratios of galaxies in the local UniverseFeb 07 2018We present the extended GALEX Arecibo SDSS Survey (xGASS), a gas fraction-limited census of the atomic (HI) gas content of 1179 galaxies selected only by stellar mass ($M_\star =10^{9}-10^{11.5} M_\odot$) and redshift ($0.01<z<0.05$). This includes new ... More
LBT/MODS spectroscopy of globular clusters in the irregular galaxy NGC 4449Feb 07 2018We present intermediate-resolution (R$\sim$1000) spectra in the $\sim$3500-10,000 \AA\ range of 14 globular clusters in the magellanic irregular galaxy NGC 4449 acquired with the Multi Object Double Spectrograph on the Large Binocular Telescope. We derived ... More
LBT/MODS spectroscopy of globular clusters in the irregular galaxy NGC 4449Feb 07 2018Feb 08 2018We present intermediate-resolution (R$\sim$1000) spectra in the $\sim$3500-10,000 A range of 14 globular clusters in the magellanic irregular galaxy NGC 4449 acquired with the Multi Object Double Spectrograph on the Large Binocular Telescope. We derived ... More
Star-formation rate in compact star-forming galaxiesFeb 07 2018We use the data for the Hbeta emission-line, far-ultraviolet (FUV) and mid-infrared 22 micron continuum luminosities to estimate star formation rates <SFR> averaged over the galaxy lifetime for a sample of about 14000 bursting compact star-forming galaxies ... More
Triggering the formation of the supergiant H II region NGC 604 in M33Feb 07 2018Formation mechanism of a supergiant H II region NGC 604 is discussed in terms of collision of H I clouds in M33. An analysis of the archival H I data obtained with the Very Large Array (VLA) reveals complex velocity distributions around NGC 604. The H ... More
An unexpected detection of bifurcated blue straggler sequences in the young globular cluster NGC 2173Feb 07 2018Bifurcated patterns of blue straggler stars in their color--magnitude diagrams have atracted significant attention. This type of special (but rare) pattern of two distinct blue straggler sequences is commonly interpreted as evidence of cluster core-collapse-driven ... More
Optical Photometric Variable Stars towards the Galactic \hii region NGC 2282Feb 07 2018We report here CCD $I$-band time-series photometry of a young (2$-$5 Myr) cluster NGC 2282 to identify and understand the variability of pre-main-sequence (PMS) stars. The $I$-band photometry, down to $\sim$ 20.5 mag, enables us to probe the variability ... More
Model Selection Using Cosmic Chronometers with Gaussian ProcessesFeb 06 2018The use of Gaussian Processes with a measurement of the cosmic expansion rate based solely on the observation of cosmic chronometers provides a completely cosmology-independent reconstruction of the Hubble constant H(z) suitable for testing different ... More
Spectrophotometric Redshifts In The Faint Infrared Grism Survey: Finding Overdensities Of Faint GalaxiesFeb 06 2018We improve the accuracy of photometric redshifts by including low-resolution spectral data from the G102 grism on the Hubble Space Telescope, which assists in redshift determination by further constraining the shape of the broadband Spectral Energy Disribution ... More
Physical and numerical stability and instability of AGN bubbles in a hot intracluster mediumFeb 06 2018While feedback from Active Galactic Nuclei (AGN) is an important heating source in the centre of galaxy clusters, it is still unclear how the feedback energy is injected into the intracluster medium (ICM) and what role different numerical approaches play. ... More
The New Numerical Galaxy Catalogue (ν^2 GC): Properties of Active Galactic Nuclei and Their Host GalaxiesFeb 06 2018We present the latest results of a semi-analytic model of galaxy formation, "New Numerical Galaxy Catalogue", which is combined with large cosmological N-body simulations. This model can reproduce statistical properties of galaxies at z < 6.0. We focus ... More
Galaxy pairs in the SDSS - XIII. The connection between enhanced star formation and molecular gas properties in galaxy mergersFeb 06 2018We investigate the connection between star formation and molecular gas properties in galaxy mergers at low redshift (z$\leq$0.06). The study we present is based on IRAM 30-m CO(1-0) observations of 11 galaxies with a close companion selected from the ... More
LeMMINGs. I. The eMERLIN legacy survey of nearby galaxies. 1.5-GHz parsec-scale radio structures and coresFeb 06 2018We present the first data release of high-resolution ($\leq0.2$ arcsec) 1.5-GHz radio images of 103 nearby galaxies from the Palomar sample, observed with the eMERLIN array, as part of the LeMMINGs survey. This sample includes galaxies which are active ... More
Blowing in the Milky Way wind: neutral hydrogen clouds tracing the Galactic nuclear outflowFeb 06 2018We present the results of a new sensitive survey of neutral hydrogen above and below the Galactic Center with the Green Bank Telescope. The observations extend up to Galactic latitude | b | < 10 deg with an effective angular resolution of 9.5' and an ... More
ASAGAO. Average Morphology of High-$z$ Dusty Star-Forming Galaxies is an Exponential-Disk ($n \simeq 1$) Harboring an AGNFeb 06 2018We present morphological properties of dusty star-forming galaxies at z=1-3 determined with high-resolution (FWHM~0"19) Atacama Large Milllimeter/submilimeter Array (ALMA) 1-mm band maps of our ASAGAO survey covering a 26-arcmin^2 area in GOODS-S and ... More
Ionized and molecular gas kinematics in a z=1.4 star-forming galaxyFeb 06 2018We present deep observations of a $z=1.4$ massive, star-forming galaxy in molecular and ionized gas at comparable spatial resolution (CO 3-2, NOEMA; H$\alpha$, LBT). The kinematic tracers agree well, indicating that both gas phases are subject to the ... More
Towards an improvement in the spectral description of central stars of planetary nebulaeFeb 06 2018Context. There are more than 3000 known Galactic planetary nebulae (PNe), but only 492 central stars of Galactic planetary nebulae (CSPN) have known spectral types. It is vital to increase this number in order to have reliable statistics, which will lead ... More
Near-infrared study of new embedded clusters in the Carina complexFeb 06 2018We analyse the nature of a sample of stellar overdensities that we found projected on the Carina complex. This study is based on 2MASS photometry and involves the photometry decontamination of field stars, elaboration of intrinsic colour-magnitude diagrams ... More
A study of two dwarf irregular galaxies with asymmetrical star formation distributionsFeb 06 2018Two dwarf irregular galaxies DDO 187 and NGC 3738 exhibit a striking pattern of star formation: intense star formation is taking place in a large region occupying roughly half of the inner part of the optical galaxy. We use data on the HI distribution ... More
AGN feedback and the origin and fate of the hot gas in early-type galaxiesFeb 06 2018A recent determination of the relationships between the X-ray luminosity of the ISM (Lx) and the stellar and total mass, for a sample of nearby early-type galaxies (ETGs), is used to investigate the origin of the hot gas, via a comparison with the results ... More
Testing modified gravity with globular clusters: the case of NGC 2419Feb 06 2018The dynamics of globular clusters has been studied in great detail in the context of general relativity as well as with modifications of gravity that strongly depart from the standard paradigm such as MOND. However, at present there are no studies that ... More
The contribution of faint AGNs to the ionizing background at z~4Feb 06 2018Finding the sources responsible for the hydrogen reionization is one of the most pressing issues in cosmology. Bright QSOs are known to ionize their surrounding neighborhood, but they are too few to ensure the required HI ionizing background. A significant ... More
The redshift of the BL Lac object TXS 0506+056Feb 06 2018The bright BL Lac object TXS 0506+056 is a most likely counterpart of the IceCube neutrino event EHE 170922A. The lack of this redshift prevents a comprehensive understanding of the modeling of the source. We present high signal-to-noise optical spectroscopy, ... More
The spectral energy distribution of the hyperluminous, hot dust-obscured galaxy W2246$-$0526Feb 06 2018Hot dust-obscured galaxies (Hot DOGs) are a luminous, dust-obscured population recently discovered in the WISE All-Sky survey. Multiwavelength follow-up observations suggest that they are mainly powered by accreting supermassive black holes (SMBHs), lying ... More
Massive stars in the SDSS-IV/APOGEE SURVEY. I- OB starsFeb 05 2018In this work we make use of DR14 APOGEE spectroscopic data to study a sample of 92 known OB stars. We developed a near-infrared semi-empirical spectral classification method that was successfully used in case of four new exemplars, previously classified ... More
The empirical Gaia G-band extinction coefficientFeb 05 2018The first Gaia data release unlocked the access to the photometric information of 1.1 billion sources in the $G$-band. Yet, given the high level of degeneracy between extinction and spectral energy distribution for large passbands such as the Gaia $G$-band, ... More
The KMOS Cluster Survey (KCS) II - The Effect of Environment on the Structural Properties of Massive Cluster Galaxies at Redshift $1.39 < z <1.61$Feb 05 2018We present results on the structural properties of massive passive galaxies in three clusters at $1.39<z<1.61$ from the KMOS Cluster Survey. We measure light-weighted and mass-weighted sizes from optical and near-infrared Hubble Space Telescope imaging ... More
Models of Tidally Induced Gas Filaments in the Magellanic StreamFeb 05 2018The Magellanic Stream and Leading Arm of HI that stretches from the Large and Small Magellanic Clouds (LMC and SMC) and over 200 degrees of the Southern sky is thought to be formed from multiple encounters between the LMC and SMC. In this scenario, most ... More
Mapping the core of the Tarantula Nebula with VLT-MUSE: I. Spectral and nebular content around R136Feb 05 2018We introduce VLT-MUSE observations of the central 2$'\times2'$ (30$\times$30 pc) of the Tarantula Nebula in the Large Magellanic Cloud. The observations provide an unprecedented spectroscopic census of the massive stars and ionised gas in the vicinity ... More
The mass-size relation of LRGs from BOSS and DECaLSFeb 05 2018We use the DECaLS DR3 survey photometry matched to the SDSS-III/BOSS DR12 spectroscopic catalog to investigate the morphology and stellar mass-size relation of luminous red galaxies (LRGs) within the CMASS and LOWZ galaxy samples in the redshift range ... More
The enhancement of rapidly quenched galaxies in distant clusters at 0.5<z<1.0Feb 05 2018We investigate the relationship between environment and galaxy evolution in the redshift range $0.5 < z < 1.0$. Galaxy overdensities are selected using a Friends-of-Friends algorithm, applied to deep photometric data in the Ultra-Deep Survey (UDS) field. ... More
PISCO: The Pmas/ppak Integral-field Supernova hosts COmpilationFeb 05 2018We present the Pmas/ppak Integral-field Supernova hosts COmpilation (PISCO) which comprises Integral Field Spectroscopy (IFS) of 232 supernova (SN) host galaxies, that hosted 272 SNe, observed over several semesters with the 3.5m telescope at the Calar ... More
The First Detection of Neutral Hydrogen in Emission in a Strong Spiral LensFeb 05 2018We report HI observations of eight spiral galaxies that are strongly lensing background sources. Our targets were selected from the Sloan WFC (Wide Field Camera) Edge-on Late-type Lens Survey (SWELLS) using the Arecibo, Karl G. Jansky Very Large Array, ... More
Discovery of distant RR Lyrae stars in the Milky Way using DECamFeb 05 2018We report the discovery of distant RR Lyrae stars, including the most distant known in the Milky Way, using data taken in the $g-$band with the Dark Energy Camera as part of the High cadence Transient Survey (HiTS; 2014 campaign). We detect a total of ... More
Intermediate-mass black holes in dwarf galaxies out to redshift $\sim$ 2.4 in the Chandra COSMOS Legacy SurveyFeb 05 2018We present a sample of 40 AGN in dwarf galaxies at redshifts $z \lesssim$ 2.4. The galaxies are drawn from the \textit{Chandra} COSMOS-Legacy survey as having stellar masses $10^{7}\leq M_{*}\leq3 \times 10^{9}$ M$_{\odot}$. Most of the dwarf galaxies ... More
ATLAS Probe: Breakthrough Science of Galaxy Evolution, Cosmology, Milky Way, and the Solar SystemFeb 05 2018ATLAS (Astrophysics Telescope for Large Area Spectroscopy) Probe is a concept for a NASA probe-class space mission, the spectroscopic follow-up to WFIRST, multiplexing its scientific return by obtaining deep 1 to 4 micron slit spectroscopy for ~90% of ... More
High-resolution IR absorption spectroscopy of polycyclic aromatic hydrocarbons in the 3 micron region: role of hydrogenation and alkylationFeb 05 2018Aims. We aim to elucidate the spectral changes in the 3 micron region that result from chemical changes in the molecular periphery of polycyclic aromatic hydrocarbons (PAHs) with extra hydrogens (H-PAHs) and methyl groups (Me-PAHs). Methods. Advanced ... More
Characterising bars in low surface brightness galaxiesFeb 05 2018In this paper, we use $\textit{B}$-band, $\textit{I}$-band, and 3.6 $\mu$m azimuthal light profiles of four low surface brightness (LSB) galaxies (UGC 628, F568-1, F568-3, F563-V2) to characterise three bar parameters: length, strength, and corotation ... More
Exploring the making of a galactic wind in the star-bursting dwarf irregular galaxy IC 10 with LOFARFeb 05 2018Low-mass galaxies are subject to strong galactic outflows, in which cosmic rays may play an important role, they can be best traced with low-frequency radio continuum observations, which are less affected by spectral ageing. We present a study of the ... More
Classifying and modelling spiral structures in hydrodynamic simulations of astrophysical discsFeb 05 2018We demonstrate numerical techniques for automatic identification of individual spiral arms in hydrodynamic simulations of astrophysical discs. Building on our earlier work, which used tensor classification to identify regions that were "spiral-like", ... More
Spinup and Disruption of Interstellar Asteroids by Mechanical Torques, and Implications for 1I/2017 U1 (`Oumuamua)Feb 05 2018The detection of the first interstellar asteroid, 1I/2017 U1 (`Oumuamua), has opened a new era for research on interstellar objects. In this paper, we study the rotational dynamics of interstellar asteroids (ISAs) of irregular shapes moving through the ... More
Multidimensional Data Driven Classification of Active GalaxiesFeb 05 2018We propose a new soft clustering scheme for classifying galaxies in different activity classes using simultaneously 4 emission-line ratios; log([NIII]/H{\alpha}), log([SII]/H{\alpha}), log([OI]/H{\alpha}) and log([OIII]/H{\beta}). We fit 20 multivariate ... More
MOCCA-SURVEY Database I: Assessing GW kick retention fractions for BH-BH mergers in globular clustersFeb 04 2018Anisotropy of gravitational wave (GW) emission results in a net momentum gained by the black hole (BH) merger product, leading to a recoil velocity up to $\sim10^3\text{ km s}^{-1}$, which may kick it out of a globular cluster (GC). We estimate GW kick ... More
Emergent Viscosity: An alternative for Dark Matter in GalaxiesFeb 04 2018Feb 06 2018We assume that the individual stars which are located at the peripheral parts of the spiral galaxies are experiencing a drag force acting upon them radially. Such a force might be produced by some sort of a dynamically generated viscous medium, and as ... More
The S-PASS view of polarized Galactic Synchrotron at 2.3 GHz as a contaminant to CMB observationsFeb 04 2018We analyze the Southern Sky emission in linear polarization at 2.3 GHz as observed by the S-band Polarization All Sky Survey S-PASS. Our purpose is to study the properties of the diffuse Galactic polarized synchrotron as a contaminant to CMB B-mode observations. ... More
FERMI transient J1544-0649: a flaring radio-weak BL LacFeb 04 2018On May 15th, 2017, the \emph{FERMI}/LAT gamma-ray telescope observed a transient source not present in any previous high-energy catalogue: J1544-0649. It was visible for two consecutive weeks, with a flux peak on May 21st. Subsequently observed by a \emph{Swift}/XRT ... More
The Distance and the near-IR extinction of the Monoceros Supernova RemnantFeb 04 2018Supernova remnants (SNRs) embody the information of the influence on dust properties by the supernova explosion. Based on the color indexes from the 2MASS photometric survey and the stellar parameters from the SDSS$-$DR12$/$APOGEE and LAMOST$-$DR2$/$LEGUE ... More
Is molecular cloud turbulence driven by external supernova explosions?Feb 03 2018We present high-resolution ($\sim$ 0.1 pc), hydrodynamical and magneto-hydrodynamical simulations to investigate whether the observed level of molecular cloud (MC) turbulence can be generated and maintained by external supernova (SN) explosions. The MCs ... More
DECam Survey for Low-Mass Stars and Substellar Objects in the UCL and LCC Subgroups of the Sco-Cen OB Association (SCOCENSUS)Feb 02 2018Using images taken with the Dark Energy Camera (DECam), the first extensive survey of low mass and substellar objects is made in the 15-20 Myr Upper Centaurus Lupus (UCL) and Lower Centaurus Crux (LCC) subgroups of the Scorpius Centaurus OB Association ... More
Seeds of Life in Space (SOLIS). III. Zooming into the methanol peak of the pre-stellar core L1544Feb 02 2018Towards the pre-stellar core L1544, the methanol (CH$_3$OH) emission forms an asymmetric ring around the core centre, where CH$_3$OH is mostly in solid form, with a clear peak 4000~au to the north-east of the dust continuum peak. As part of the NOEMA ... More
On the origin of phosphorus nitride in star-forming regionsFeb 02 2018We present multi-transition observations of PN towards a sample of nine massive dense cores in different evolutionary stages. Using transitions with different excitation conditions, we have found for the first time that the excitation temperatures of ... More
A Statistical Study of Massive Cluster-Forming ClumpsFeb 02 2018We report results of the observations of 15 regions in several molecular lines for a statistical study of massive cluster-forming clumps. We identified 24 clumps based on the C18O (J=1-0) data obtained by the NRO 45 m telescope, and found that 16 of them ... More
Resolving the Disc-Halo Degeneracy I: A Look at NGC 628Feb 01 2018The decomposition of the rotation curve of galaxies into contribution from the disc and dark halo remains uncertain and depends on the adopted mass to light ratio (M/L) of the disc. Given the vertical velocity dispersion of stars and disc scale height, ... More
Mapping UV Properties Throughout the Cosmic Horseshoe: Lessons from VLT-MUSEFeb 01 2018We present the first spatially-resolved rest-frame UV study of the gravitationally lensed galaxy, the 'Cosmic Horseshoe' (J1148+1930) at z=2.38. Our gravitational lens model shows that the system is made up of four star-forming regions, each ~4-8 kpc^2 ... More
The disc origin of the Milky Way bulge: II. Dissecting the chemo-morphological relations using N-body simulations and APOGEEFeb 01 2018There is a long-standing debate on the origin of the metal-poor stellar populations of the Milky Way (MW) bulge, with the two leading scenarios being that these populations are either i) part of a classical metal-poor spheroid or ii) the same population ... More
Observational constraints on the physical nature of submillimetre source multiplicity: chance projections are commonFeb 01 2018Interferometric observations have demonstrated that a significant fraction of single-dish submillimetre (submm) sources are blends of multiple submm galaxies (SMGs), but the nature of this multiplicity, i.e. whether the galaxies are physically associated ... More
ALMA's Polarized View of 10 Protostars in the Perseus Molecular CloudFeb 01 2018We present 870 $\mu$m ALMA dust polarization observations of 10 young Class 0/I protostars in the Perseus Molecular Cloud. At $\sim$ 0.35$"$ (80 au) resolution, all of our sources show some degree of polarization, with most (9/10) showing significantly ... More
Outflows in the Narrow Line Region of Bright Seyfert Galaxies - I: GMOS-IFU DataFeb 01 2018We present two-dimensional maps of emission-line fluxes and kinematics, as well as of the stellar kinematics of the central few kpc of five bright nearby Seyfert galaxies -- Mrk\,6, Mrk\,79, Mrk\,348, Mrk\,607 and Mrk\,1058 -- obtained from observations ... More
EDIBLES II. On the detectability of C60+ bandsFeb 01 2018Gas phase spectroscopic laboratory experiments for the buckminsterfullerene cation C60+ resulted in accurate rest wavelengths for five C60+ transitions that have been compared with diffuse interstellar bands (DIBs) in the near infra-red. Detecting these ... More
The Strong Gravitationally Lensed Herschel Galaxy HLock01: Optical Spectroscopy Reveals a Close Galaxy Merger with Evidence of Inflowing GasFeb 01 2018The submillimeter galaxy (SMG) HERMES J105751.1+573027 (hereafter HLock01) at z = 2.9574 +/- 0.0001 is one of the brightest gravitationally lensed sources discovered in the Herschel Multi-tiered Extragalactic Survey. Apart from the high flux densities ... More
The population of single and binary white dwarfs of the Galactic bulgeFeb 01 2018Recent Hubble Space Telescope observations have unveiled the white dwarf cooling sequence of the Galactic bulge. Although the degenerate sequence can be well fitted employing the most up-to-date theoretical cooling sequences, observations show a systematic ... More
Thirty-fold: Extreme gravitational lensing of a quiescent galaxy at $z=1.6$Feb 01 2018We report the discovery of eMACSJ1341-QG-1, a quiescent galaxy at $z=1.594$ located behind the massive galaxy cluster eMACSJ1341.9$-$2442 ($z=0.835$). The system was identified as a gravitationally lensed triple image in Hubble Space Telescope images ... More
A whirling plane of satellite galaxies around Centaurus A challenges cold dark matter cosmologyJan 31 2018The Milky Way and Andromeda galaxy are each surrounded by a thin plane of satellite galaxies that may be corotating. Cosmological simulations predict that most satellite galaxy systems are close to isotropic with random motions, so those two well-studied ... More
Asymmetric emission of the [OIII]$λ$5007 profile in narrow-line Seyfert 1 galaxiesJan 31 2018Many active galactic nuclei (AGN) and particularly narrow-line Seyfert 1 (NLS1) galaxies, usually exhibit blueshifts and blue wings in several emission lines, which are mainly associated with outflows and strong winds. In order to study the radial velocity ... More
The ALFALFA HI mass function: A dichotomy in the low-mass slope and a locally suppressed 'knee' massJan 31 2018We present the most precise measurement of the $z = 0$ HI mass function (HIMF) to date based on the final catalogue of the ALFALFA (Arecibo Legacy Fast ALFA) blind HI survey of the nearby Universe. The Schechter function fit has a `knee' mass $\log (M_{*}\,h^{2}_{70}/\mathrm{M_{\odot}}) ... More
Revealing the velocity structure of the filamentary nebula in NGC 1275 in its entiretyJan 31 2018We have produced for the first time a detailed velocity map of the giant filamentary nebula surrounding NGC 1275, the Perseus cluster's brightest galaxy, and revealed a previously unknown rich velocity structure across the entire nebula. We present new ... More
Tracing 3D distribution of magnetic fields with gradients of synchrotron polarizationJan 31 2018In this paper, we describe a new technique for probing galactic and extragalactic 2D and 3D distribution of magnetic field using synchrotron polarization. Fluctuations of magnetic field are elongated along the ambient magnetic field directions. As a result, ... More
Understanding the strong intervening OVI absorber at z$_{abs}$ ~0.93 towards PG1206+459Jan 31 2018Feb 06 2018We have obtained new observations of the partial Lyman limit absorber at \zabs$=0.93$ towards quasar PG~1206+459, and revisit its chemical and physical conditions. The absorber, with $ N(HI) \sim 10^{17.0}$ ~\sqcm\ and absorption lines spread over $\gtrsim$1000~\kms\ ... More
Diagnostics of turbulence properties through Velocity Gradient Amplitudes: Theory and ObservationsJan 31 2018Based on the properties of magneto-hydrodynamic (MHD) turbulence, the recent development of the Velocity Gradient Technique (VGT) allows observers to trace magnetic field directions using spectroscopic information. In this paper, we explore how the amplitudes ... More
The MASSIVE Survey - X. Stellar Velocity Features and Misalignment between Kinematic and Photometric Axes in Massive Early-Type GalaxiesJan 31 2018We use spatially resolved two-dimensional stellar velocity maps over a $107''\times 107''$ field of view to investigate the kinematic features of 90 early-type galaxies above stellar mass $10^{11.5}M_\odot$ in the MASSIVE survey. We measure the misalignment ... More
Spiral arms, warping, and clumps formation in the Galactic center young stellar diskJan 31 2018The Galactic center of the Milky-Way harbors a massive black hole (BH) orbited by a diverse population of young and old stars. A significant fraction of the youngest stars ($\sim4-7$ Myr) reside in a thin stellar disk with puzzling properties; the disk ... More
Detection of an OH 1665-MHz Maser in M33Jan 31 2018We report one OH 1665-MHz detection in new observations with the NSF's Karl G. Jansky Very Large Array. To the authors' knowledge, this is the first OH maser detection in M33. The source occurs at a position of $\alpha=23.50069(9)^{\circ}$ and $\delta ... More
Exploring the Chemical Composition and Double Horizontal Branch of the Bulge Globular Cluster NGC 6569Jan 31 2018Photometric and spectroscopic analyses have shown that the Galactic bulge cluster Terzan 5 hosts several populations with different metallicities and ages that manifest as a double red horizontal branch (HB). A recent investigation of the massive bulge ... More
Magnetic fields at the onset of high-mass star formationJan 31 2018Context: The importance of magnetic fields at the onset of star formation related to the early fragmentation and collapse processes is largely unexplored today. Aims: We want to understand the magnetic field properties at the earliest evolutionary stages ... More
FirstLight II: Star formation rates of primeval galaxies from z=5-15Jan 31 2018In the FirstLight project, we have used ~300 cosmological, zoom-in simulations to determine the star-formation histories of distinct first galaxies with stellar masses between Ms=10^6 and 3 x 10^9 Msun during cosmic dawn (z=5-15). The evolution of the ... More
Disks and outflows in the S255IR area of high mass star formation from ALMA observationsJan 31 2018We describe the general structure of the well known S255IR high mass star forming region, as revealed by our recent ALMA observations. The data indicate a physical relation of the major clumps SMA1 and SMA2. The driving source of the extended high velocity ... More
Molecular Gas Toward the Gemini OB1 Molecular Cloud Complex II: CO Outflow Candidates with Possible WISE AssociationsJan 31 2018We present a large scale survey of CO outflows in the Gem OB1 molecular cloud complex and its surroundings using the Purple Mountain Observatory Delingha 13.7 m telescope. A total of 198 outflow candidates were identified over a large area ($\sim$ 58.5 ... More
Chemical abundances of primary stars in the Sirius-like binary systemsJan 31 2018Study of primary stars lying in Sirius-like systems with various masses of WD companions and orbital separations is one of the key aspects to understand the origin and nature of Barium (Ba) stars. In this paper, based on high resolution and high S/N spectra, ... More
The Detection of Hot Cores and Complex Organic Molecules in the Large Magellanic CloudJan 31 2018We report the first extragalactic detection of the complex organic molecules (COMs) dimethyl ether (CH$_3$OCH$_3$) and methyl formate (CH$_3$OCHO) with the Atacama Large Millimeter/submillimeter Array (ALMA). These COMs together with their parent species ... More
Herschel Spectroscopy of the Taffy Galaxies (UGC 12914/12915 = VV 254): Enhanced [C II] emission in the collisionally-formed bridgeJan 30 2018Using the PACS and SPIRE spectrometers on-board Herschel, we obtained observations of the Taffy galaxies (UGC 12914/12915) and bridge. The Taffy system is believed to be the result of a face-on collision between two gas-rich galaxies, in which the stellar ... More
MMT Spectroscopy of Supernova Remnant Candidates in M33Jan 30 2018To date, over 220 emission nebulae in M33 have been identified as supernova remnants (SNRs) or SNR candidates, principally through [SII]:Halpha line ratios that are elevated compared to those in H II regions. In many cases, the determination of a high ... More