Results for "J. Bally"

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An S-shaped outflow from IRAS 03256+3055 in NGC 1333Dec 01 2004The IRAS source 03256+3055 in the NGC 1333 star forming region is associated with extended sub-millimeter emission of complex morphology, showing multiple clumps. One of these is found to coincide with the driving source of a bipolar jet of S-shaped morphology ... More
Capture Formed Binaries via Encounters with Massive ProtostarsOct 20 2006Most massive stars are found in the center of dense clusters, and have a companion fraction much higher than their lower mass siblings; the massive stars of the Trapezium core in Orion have ~ 1.5 companions each. This high multiplicity could be a consequence ... More
A generic construction for high order approximation schemes of semigroups using random gridsMay 21 2019Our aim is to construct high order approximation schemes for general semigroups of linear operators $P_{t},t\geq 0$. In order to do it, we fix a time horizon $T $ and the discretization steps $h_{l}=\frac{T}{n^{l}},l\in \mathbb{N}$ and we suppose that ... More
Herschel observations of the Sgr B2 cores: Hydrides, warm CO, and cold dustJul 01 2013Sagittarius B2 (Sgr B2) is one of the most massive and luminous star-forming regions in the Galaxy and shows chemical and physical conditions similar to those in distant extragalactic starbursts. We present large-scale far-IR/submm photometric images ... More
A Pulsed, Precessing Jet in Cepheus AFeb 13 2009We present near-infrared H2, radio CO, and thermal infrared observations of the nearby massive star-forming region Cepheus A (Cep A). From H2 bow shocks arranged along four distinct jet axes, we infer that the massive protostellar source HW2 drives a ... More
Turbulence sets the initial conditions for star formation in high-pressure environmentsSep 03 2014Despite the simplicity of theoretical models of supersonically turbulent, isothermal media, their predictions successfully match the observed gas structure and star formation activity within low-pressure (P/k < 10^5 K cm^-3) molecular clouds in the solar ... More
A cluster in the making: ALMA reveals the initial conditions for high-mass cluster formationJan 29 2015G0.253+0.016 is a molecular clump that appears to be on the verge of forming a high mass, Arches-like cluster. Here we present new ALMA observations of its small-scale (~0.07 pc) 3mm dust continuum and molecular line emission. The data reveal a complex ... More
Convergence in distribution norms in the CLT for non identical distributed random variablesJun 06 2016Nov 09 2017We study the convergence in distribution norms in the Central Limit Theorem for non identical distributed random variables that is $$ \varepsilon_{n}(f):={\mathbb{E}}\Big(f\Big(\frac 1{\sqrt n}\sum_{i=1}^{n}Z_{i}\Big)\Big)-{\mathbb{E}}\big(f(G)\big)\rightarrow ... More
And in the Darkness Bind Them: Equatorial Rings, B[e] Supergiants, and the Waists of Bipolar NebulaeMay 21 2007We report the discovery of two new circumstellar ring nebulae in the western Carina Nebula. The brighter object, SBW1, resembles a lidless staring eye and encircles a B1.5 Iab supergiant. Its size is identical to the inner ring around SN1987A, but SBW1's ... More
The link between solenoidal turbulence and slow star formation in G0.253+0.016Sep 28 2016Star formation in the Galactic disc is primarily controlled by gravity, turbulence, and magnetic fields. It is not clear that this also applies to star formation near the Galactic Centre. Here we determine the turbulence and star formation in the CMZ ... More
The link between turbulence, magnetic fields, filaments, and star formation in the Central Molecular Zone cloud G0.253+0.016Sep 19 2016Star formation is primarily controlled by the interplay between gravity, turbulence, and magnetic fields. However, the turbulence and magnetic fields in molecular clouds near the Galactic Center may differ substantially from spiral-arm clouds. Here we ... More
Velocity Field Statistics in Star-Forming Regions. I. Centroid Velocity ObservationsOct 27 1998Apr 21 1999The probability density functions (pdfs) of molecular line centroid velocity fluctuations and fluctuation differences at different spatial lags are estimated for several nearby molecular clouds with active internal star formation. The data consist of ... More
There are no starless massive proto-clusters in the first quadrant of the GalaxyAug 20 2012Aug 22 2012We search the lambda = 1.1 mm Bolocam Galactic Plane Survey for clumps containing sufficient mass to form ~10^4 M\odot star clusters. 18 candidate massive proto-clusters are identified in the first Galactic quadrant outside of the central kiloparsec. ... More
The Peculiar Nebula Simeis 57: I. Ionized Gas and Dust ExtinctionNov 19 2002We present high resolution radio continuum maps of the Galactic nebula Simeis 57 (= HS 191 = G 80.3+4.7) made with the WSRT and the DRAObservatory at frequencies of 609, 1412 and 1420 MHz. At optical and at radio wavelengths, the nebula has a peculiar ... More
Proper Motions of the HH 47 Jet Observed with the Hubble Space TelescopeJul 22 2005We present a proper motion study of the shock waves within the classic stellar jet HH 47 based on Hubble Space Telescope H-alpha and [S II] images of the region taken over two epochs. Individual knots within the jet and in the bow shock/Mach disk working ... More
A new star-forming region in Canis MajorApr 28 2016A new southern star-formation region, located at an estimated distance of ~1.5 kpc in the Lynds 1664 dark cloud in Canis Major, is described. Lynds 1664 contains several compact star clusters, small stellar groups, and young stars associated with reflection ... More
Multiple CO Outflows in Circinus: The Churning of a Molecular CloudNov 05 1998We present a millimeter wave study of a cluster of bipolar CO outflows embedded in the western end of the Circinus molecular cloud complex, G317-4, that is traced by very high optical extinction. For an assumed distance of 700 pc, the entire Circinus ... More
The time evolution of HH 1 from four epochs of HST imagesMar 04 2016We present an analysis of four epochs of H$\alpha$ and [S II] $\lambda\lambda$ 6716/6731 HST images of HH 1. For determining proper motions we explore a new method based on analysis of spatially degraded images obtained convolving the images with wavelet ... More
A Survey of Irradiated Pillars, Globules, and Jets in the Carina NebulFeb 12 2015We present wide-field, deep narrowband H$_2$, Br$\gamma$, H$\alpha$, [S II], [O III], and broadband I and K-band images of the Carina star formation region. The new images provide a large-scale overview of all the H$_2$ and Br$\gamma$ emission present ... More
A causal inference approach to network meta-analysisJun 04 2015Aug 11 2016While standard meta-analysis pools the results from randomized trials that compare two treatments, network meta-analysis aggregates the results of randomized trials comparing a wider variety of treatment options. However, it is unclear whether the aggregation ... More
Cleaning up Eta Carinae: Detection of Ammonia in the HomunculusMay 22 2006We report the first detection of ammonia in the Homunculus nebula around eta Carinae, which is also the first detection of emission from a polyatomic molecule in this or any other luminous blue variable (LBV) nebula. Observations of the NH3 (J,K)=(3,3) ... More
Thermal Feedback in the high-mass star and cluster forming region W51Apr 05 2017May 17 2017High-mass stars have generally been assumed to accrete most of their mass while already contracted onto the main sequence, but this hypothesis has not been observationally tested. We present ALMA observations of a 3 x 1.5 pc area in the W51 high-mass ... More
Molecular gas kinematics within the central 250 pc of the Milky WayJan 14 2016Feb 10 2016Using spectral-line observations of HNCO, N2H+, and HNC, we investigate the kinematics of dense gas in the central ~250 pc of the Galaxy. We present SCOUSE (Semi-automated multi-COmponent Universal Spectral-line fitting Engine), a line fitting algorithm ... More
Young massive star cluster formation in the Galactic Centre is driven by global gravitational collapse of high-mass molecular cloudsMar 14 2019Young massive clusters (YMCs) are the most compact, high-mass stellar systems still forming at the present day. The precursor clouds to such systems are, however, rare due to their large initial gas mass reservoirs and rapid dispersal timescales due to ... More
Overview of the Orion ComplexNov 29 2008The Orion star formation complex is the nearest region of on-going star formation that continues to produce both low and high mass stars. Orion is discussed in the larger context of star formation in the Solar vicinity over the last 100 Myr. The Orion ... More
Lower bounds for the density of locally elliptic Itô processesFeb 28 2007We give lower bounds for the density $p_T(x,y)$ of the law of $X_t$, the solution of $dX_t=\sigma (X_t) dB_t+b(X_t) dt,X_0=x,$ under the following local ellipticity hypothesis: there exists a deterministic differentiable curve $x_t, 0\leq t\leq T$, such ... More
Outflows from Massive StarsDec 12 2007The properties of outflows powered by massive stars are reviewed with an emphasis on the nearest examples, Orion and Cepheus-A. The Orion OMC1 outflow may have been powered by the dynamical decay of a non-hierarchical massive star system that resulted ... More
Star formation in a high-pressure environment: An SMA view of the Galactic centre dust ridgeNov 02 2017The star formation rate in the Central Molecular Zone (CMZ) is an order of magnitude lower than predicted according to star formation relations that have been calibrated in the disc of our own and nearby galaxies. Understanding how and why star formation ... More
G0.253+0.016: a molecular cloud progenitor of an Arches-like clusterNov 14 2011Young massive clusters (YMCs) with stellar masses of 10^4 - 10^5 Msun and core stellar densities of 10^4 - 10^5 stars per cubic pc are thought to be the `missing link' between open clusters and extreme extragalactic super star clusters and globular clusters. ... More
Spitzer Observations of the HII Region NGC 2467: An Analysis of Triggered Star FormationNov 09 2007Jun 23 2009We present new Spitzer Space Telescope observations of the region NGC 2467, and use these observations to determine how the environment of an HII region affects the process of star formation. Our observations comprise IRAC (3.6, 4.5, 5.8, and 8.0 um) ... More
A Near Infrared Laser Frequency Comb for High Precision Doppler Planet SurveysFeb 27 2010We discuss the laser frequency comb as a near infrared astronomical wavelength reference, and describe progress towards a near infrared laser frequency comb at the National Institute of Standards and Technology and at the University of Colorado where ... More
SPIRITS 15c and SPIRITS 14buu: Two Obscured Supernovae in the Nearby Star-Forming Galaxy IC 2163Sep 14 2016SPIRITS---SPitzer InfraRed Intensive Transients Survey---is an ongoing survey of nearby galaxies searching for infrared (IR) transients with Spitzer/IRAC. We present the discovery and follow-up observations of one of our most luminous ($M_{[4.5]} = -17.1\pm0.4$ ... More
Evidence for dust grain growth in young circumstellar disksApr 27 2001Hundreds of circumstellar disks in the Orion nebula are being rapidly destroyed by the intense ultraviolet radiation produced by nearby bright stars. These young, million-year-old disks may not survive long enough to form planetary systems. Nevertheless, ... More
Protoplanetary Disks in the Orion OMC1 Region Imaged with ALMAApr 11 2016We present ALMA observations of the Orion Nebula that cover the OMC1 outflow region. Our focus in this paper is on compact emission from protoplanetary disks. We mosaicked a field containing $\sim 600$ near-IR-identified young stars, around which we can ... More
Explosive Outflows Powered by the Decay of Non-Hierarchical Multiple Systems of Massive Stars: Orion BN/KLNov 23 2010The explosive BN/KL outflow emerging from OMC1 behind the Orion Nebula may have been powered by the dynamical decay of a non-hierarchical multiple system $\sim$500 years ago that ejected the massive stars I, BN, and source n, with velocities of about ... More
Early stage massive star formation near the Galactic Center: Sgr CSep 02 2013We present near-infrared spectroscopy and 1 mm line and continuum observations of a recently identified site of high mass star formation likely to be located in the Central Molecular Zone near Sgr C. Located on the outskirts of the massive evolved HII ... More
Nested shells reveal the rejuvenation of the Orion-Eridanus superbubbleJun 08 2015The Orion-Eridanus superbubble is the prototypical superbubble due to its proximity and evolutionary state. Here, we provide a synthesis of recent observational data from WISE and Planck with archival data, allowing to draw a new and more complete picture ... More
Collisionally excited filaments in HST H$α$ and H$β$ images of HH~1/2Nov 28 2014We present new H$\alpha$ and H$\beta$ images of the HH~1/2 system, and we find that the H$\alpha$/H$\beta$ ratio has high values in ridges along the leading edges of the HH~1 bow shock and of the brighter condensations of HH~2. These ridges have H$\alpha$/H$\beta=4\to ... More
Star formation rates on global and cloud scales within the Galactic CentreSep 27 2016The environment within the inner few hundred parsecs of the Milky Way, known as the "Central Molecular Zone" (CMZ), harbours densities and pressures orders of magnitude higher than the Galactic Disc; akin to that at the peak of cosmic star formation (Kruijssen ... More
Distributed star formation throughout the Galactic Center cloud Sgr B2Jan 15 2018We report ALMA observations with resolution $\approx0.5$" at 3 mm of the extended Sgr B2 cloud in the Central Molecular Zone (CMZ). We detect 271 compact sources, most of which are smaller than 5000 AU. By ruling out alternative possibilities, we conclude ... More
Chandra Study of Young Stellar Objects in the NGC 1333 Star-forming CloudApr 15 2002NGC 1333, a highly active star formation region within the Perseus molecular cloud complex, has been observed with the ACIS-I detector on board the Chandra X-ray Observatory. In our image with a sensitivity limit of ~ 1e28 erg/s, we detect 127 X-ray sources, ... More
The time evolution of HH~2 from four epochs of HST imagesOct 06 2016We have analyzed four epochs of H$\alpha$ and [S~II] HST images of the HH~1/2 outflow (covering a time interval from 1994 to 2014) to determine proper motions and emission line fluxes of the knots of HH~2. We find that our new proper motions agree surprisingly ... More
X-rays from HH210 in the Orion nebulaJan 23 2006We report the detection during the Chandra Orion Ultradeep Project (COUP) of two soft, constant, and faint X-ray sources associated with the Herbig-Haro object HH210. HH210 is located at the tip of the NNE finger of the emission line system bursting out ... More
Cool Stars in Hot PlacesApr 08 2007During the last three decades, evidence has mounted that star and planet formation is not an isolated process, but is influenced by current and previous generations of stars. Although cool stars form in a range of environments, from isolated globules ... More
A 3D view of the outflow in the Orion Molecular Cloud 1 (OMC-1)Mar 14 2012The fast outflow emerging from a region associated with massive star formation in the Orion Molecular Cloud 1 (OMC-1), located behind the Orion Nebula, appears to have been set in motion by an explosive event. Here we study the structure and dynamics ... More
Stellar Encounters with Massive Star-Disk SystemsAug 02 2006The dense, clustered environment in which massive stars form can lead to interactions with neighboring stars. It has been hypothesized that collisions and mergers may contribute to the growth of the most massive stars. In this paper we extend the study ... More
Binary Capture Rates for Massive ProtostarsApr 09 2007The high multiplicity of massive stars in dense, young clusters is established early in their evolution. The mechanism behind this remains unresolved. Recent results suggest that massive protostars may capture companions through disk interactions with ... More
Regularization properties of the 2D homogeneous Boltzmann equation without cutoffNov 13 2009Nov 16 2009We consider the 2-dimensional spatially homogeneous Boltzmann equation for hard potentials. We assume that the initial condition is a probability measure that has some exponential moments and is not a Dirac mass. We prove some regularization properties: ... More
Irradiated Herbig-Haro Jets in the Orion Nebula and Near NGC 1333Sep 22 2000We report the discovery of a dozen Herbig-Haro jets illuminated by the Lyman continuum and/or softer far-ultraviolet radiation fields of nearby high mass stars. Five irradiated outflows lie in the outer parts of the Orion Nebula and seven lie near the ... More
Integration by parts formula with respect to jump times for stochastic differential equationsApr 19 2010We establish an integration by parts formula based on jumps times in an abstract framework in order to study the regularity of the law for processes solution of stochastic differential equations with jumps.
Transfer of regularity for Markov semigroupsMay 15 2019We study the regularity of a Markov semigroup $(P_t)_{t>0}$, that is, when $P_t(x,dy)=p_t(x,y)dy$ for a suitable smooth function $p_t(x,y)$. This is done by transferring the regularity from an approximating Markov semigroup sequence $(P^n_t)_{t>0}$, $n\in\mathbb{N}$, ... More
A Herschel study of YSO evolutionary stages and formation timelines in two fields of the Hi-GAL surveyMay 11 2010We present a first study of the star-forming compact dust condensations revealed by Herschel in the two 2 \times 2 \degr Galactic Plane fields centered at [l;b] = [30\degr; 0 \degr] and [l;b] = [59\degr; 0 \degr], respectively, and observed during the ... More
Large Area Mapping at 850 Microns. V. Analysis of the Clump Distribution in the Orion A South Molecular CloudSep 06 2006We present results from a 2300 arcmin^2 survey of the Orion A molecular cloud at 450 and 850 micron using the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. The region mapped lies directly south of the OMC1 cloud ... More
Discovery of a candidate protoplanetary disk around the embedded source IRc9 in OrionFeb 08 2005We report the detection of spatially-extended mid-infrared emission around the luminous embedded star IRc9 in OMC-1, as seen in 8.8, 11.7, and 18.3 micron images obtained with T-ReCS on Gemini South. The extended emission is asymmetric, and the morphology ... More
Accretion of Jupiter's atmosphere from a supernova-contaminated molecular cloudDec 14 2011If Jupiter and the Sun both formed directly from the same well-mixed proto-solar nebula, then their atmospheric compositions should be similar. However, direct sampling of Jupiter's troposphere indicates that it is enriched in elements such as C, N, S, ... More
On the distance between probability density functionsNov 29 2013We give estimates of the distance between the densities of the laws of two functionals $F$ and $G$ on the Wiener space in terms of the Malliavin-Sobolev norm of $F-G.$ We actually consider a more general framework which allows one to treat with similar ... More
An Invariance Principle for Stochastic Series II. Non Gaussian LimitsJul 13 2016We study the convergence in total variation distance for series of the form $$ S_{N}(c,Z)=\sum_{l=1}^{N}\sum_{i_{1}<\cdots<i_{l}}c(i_{1},...,i_{l})Z_{i_{1}}\cdots Z_{i_{l}}, $$ where $Z_{k},k\in {\mathbb{N}}$ are independent centered random variables ... More
Photoevaporation of Protoplanetary DisksJul 23 2008We present HST/NICMOS Paschen alpha images and low and high resolution IRS spectra of photoevaporating disk-tail systems originally detected at 24 micron near O stars. We find no Paschen alpha emission in any of the systems. The resulting upper limits ... More
High-resolution near-infrared imaging of the Orion 114-426 silhouette diskOct 31 1997We present the first high-resolution near-infrared images of the edge-on silhouette circumstellar disk, Orion 114-426, made using NICMOS on the Hubble Space Telescope. Images taken against the bright nebular background of the ionized hydrogen Pa$\alpha$ ... More
The Birth of High Mass Stars: Accretion and/or Mergers?Feb 23 2005The observational consequences of the merger scenario for massive star formation are explored and contrasted with the gradual accumulation of mass by accretion. Protostellar mergers may produce high luminosity infrared flares lasting years to centuries ... More
Positivity and lower bounds for the density of Wiener functionalsApr 29 2010Sep 19 2012We consider a functional on the Wiener space which is smooth and not degenerated in Malliavin sense and we give a criterion of strict positivity of the density. We also give lower bounds for the density. These results are based on the representation of ... More
Riesz transform and integration by parts formulas for random variablesNov 13 2009Apr 29 2010We use integration by parts formulas to give estimates for the $L^p$ norm of the Riesz transform. This is motivated by the representation formula for conditional expectations of functionals on the Wiener space already given in Malliavin and Thalmaier. ... More
Regularity of probability laws by using an interpolation methodOct 31 2012We study the problem of the existence and regularity of a probability density in an abstract framework based on a "balancing" with approximating absolutely continuous laws. Typically, the absolutely continuous property for the approximating laws can be ... More
Total variation distance between stochastic polynomials and invariance principlesMay 15 2017The goal of this paper is to estimate the total variation distance between two general stochastic polynomials. As a consequence one obtains an invariance principle for such polynomials. This generalizes known results concerning the total variation distance ... More
An 80 pc Long Massive Molecular Filament in the Galactic Mid-PlaneAug 22 2012The ubiquity of filaments in star forming regions on a range of scales is clear, yet their role in the star formation process remains in question. We suggest that there are distinct classes of filaments which are responsible for their observed diversity ... More
Convergence and regularity of probability laws by using an interpolation methodSep 10 2014In [18] Fournier and Printems establish a methodology which allows to prove the absolute continuity of the law of the solution of some stochastic equations with H\"{o}lder continuous coefficients. This is of course out of reach by using already classical ... More
An invariance principle for stochastic series I. Gaussian limitsOct 13 2015We study invariance principles and convergence to a Gaussian limit for stochastic series of the form $S(c,Z)=\sum_{m=1}^{\infty }\sum_{\alpha _{1}<...<\alpha _{m}}c(\alpha _{1},...,\alpha _{m})\prod_{i=1}^{m}Z_{\alpha _{i}}$ where $Z_{k}$, $k\in \mathbb{N}$, ... More
Tubes estimates for diffusion processes under a local Hörmander condition of order oneFeb 21 2012We consider a diffusion process $X_{t}$ and a skeleton curve $x_{t}(\phi)$ and we give a lower bound for $P(\sup_{t\leq T}d(X_{t},x_{t}(\phi))\leq R)$. This result is obtained under the hypothesis that the strong H\"{o}rmander condition of order one (which ... More
Integration by parts formula and applications to equations with jumpsNov 16 2009We establish an integration by parts formula in an abstract framework in order to study the regularity of the law for processes solution of stochastic differential equations with jumps, including equations with discontinuous coefficients for which the ... More
Asymptotic development for the CLT in total variation distanceJul 03 2014Apr 11 2016The aim of this paper is to study the asymptotic expansion in total variation in the Central Limit Theorem when the law of the basic random variable is locally lower-bounded by the Lebesgue measure (or equivalently, has an absolutely continuous component): ... More
Regularity of Wiener functionals under a Hörmander type condition of order oneJul 15 2013Sep 11 2014We study the local existence and regularity of the density of the law of a functional on the Wiener space which satisfies a criterion that generalizes the H\"ormander condition of order one (that is, involving the first order Lie brackets) for diffusion ... More
The Bolocam Galactic Plane Survey. XI. Temperatures and Substructure of Galactic Clumps Based on 350 micron ObservationsJan 23 2015Apr 02 2015We present 107 maps of continuum emission at 350 microns from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with 3 additional maps covering star forming regions in the outer Galaxy. ... More
What controls star formation in the central 500 pc of the Galaxy?Mar 25 2013Mar 12 2014The star formation rate (SFR) in the Central Molecular Zone (CMZ, i.e. the central 500 pc) of the Milky Way is lower by a factor of >10 than expected for the substantial amount of dense gas it contains, which challenges current star formation theories. ... More
X-ray Emission from Orion Nebula Cluster Stars with Circumstellar Disks and JetsJun 27 2005We investigate the X-ray and near-infrared emission properties of a sample of pre-main sequence (PMS) stellar systems in the Orion Nebula Cluster (ONC) that display evidence for circumstellar disks (``proplyds'') and optical jets in Hubble Space Telescope ... More
Candidate super star cluster progenitor gas clouds possibly triggered by close passage to Sgr A*Apr 08 2013Super star clusters are the end product of star formation under the most extreme conditions. As such, studying how their final stellar populations are assembled from their natal progenitor gas clouds can provide strong constraints on star formation theories. ... More
Bounds on Stock Price probability distributions in Local-Stochastic Volatility modelsJun 16 2010We show that in a large class of stochastic volatility models with additional skew-functions (local-stochastic volatility models) the tails of the cumulative distribution of the log-returns behave as exp(-c|y|), where c is a positive constant depending ... More
A 100-parsec elliptical and twisted ring of cold and dense molecular clouds revealed by Herschel around the Galactic CenterMay 27 2011Thermal images of cold dust in the Central Molecular Zone of the Milky Way, obtained with the far-infrared cameras on-board the Herschel satellite, reveal a 3x10^7 solar masses ring of dense and cold clouds orbiting the Galactic Center. Using a simple ... More
A probabilistic interpretation of the parametrix methodOct 23 2015In this article, we introduce the parametrix technique in order to construct fundamental solutions as a general method based on semigroups and their generators. This leads to a probabilistic interpretation of the parametrix method that is amenable to ... More
Characterizing Precursors to Stellar Clusters with HerschelJan 24 2011Context: Despite their profound effect on the universe, the formation of massive stars and stellar clusters remains elusive. In the past decade, compelling evidence has emerged that suggests Infrared Dark Clouds (IRDCs) may be precursors to stellar clusters. ... More
`Tail-end' Bondi-Hoyle accretion in young star clusters: Implications for disks, planets, and starsApr 03 2008Young stars orbiting in the gravitational potential well of forming star clusters pass through the cluster's dense molecular gas and can experience Bondi-Hoyle accretion from reservoirs outside their individual protostellar cloud cores. Accretion can ... More
Can photo-evaporation trigger planetesimal formation?Nov 23 2004Apr 05 2005We propose that UV radiation can stimulate the formation of planetesimals in externally-illuminated protoplanetary disks. We present a numerical model of disk evolution including vertical sedimentation and photo-evaporation by an external O or B star. ... More
A Highly Collimated Jet from the Red Square Nebula, MWC 922Jan 24 2019Deep, narrow-band \Ha\ and 6584 \AA\ [\Nii ] CCD images of the peculiar, infrared excess B[e] star MWC~922 reveal a collimated, bipolar jet orthogonal to the previously detected extended nebula. The jet consists of a pair of $\sim$0.15 pc segments on ... More
A Disk Shadow Around the Young Star ASR 41 in NGC 1333Dec 10 2003We present images of the young stellar object ASR 41 in the NGC 1333 star forming region at the wavelengths of H_alpha and [SII] and in the I, J, H, and K-bands. ASR 41 has the near-infrared morphology of an edge-on disk object, but appears an order of ... More
The Formation and Early Evolution of Young Massive ClustersJan 16 2014We review the formation and early evolution of the most massive and dense young stellar clusters, focusing on the role they can play in our understanding of star and planet formation as a whole. Young massive cluster (YMC) progenitor clouds in the Galactic ... More
Jets and Outflows From Star to Cloud: Observations Confront TheoryFeb 14 2014In this review we focus on the role jets and outflows play in the star and planet formation process. Our essential question can be posed as follows: are jets/outflows merely an epiphenomenon associated with star formation or do they play an important ... More
The Bolocam Galactic Plane Survey. VIII. A Mid-Infrared Kinematic Distance Discrimination MethodApr 16 2013We present a new distance estimation method for dust-continuum-identified molecular cloud clumps. Recent (sub-)millimeter Galactic plane surveys have cataloged tens of thousands of these objects, but detailed study of their physical properties requires ... More
The Bolocam Galactic Plane Survey IX: Data Release 2 and Outer Galaxy ExtensionMay 24 2013Jul 27 2013We present a re-reduction and expansion of the Bolocam Galactic Plane Survey, first presented by Aguirre et al. (2011) and Rosolowsky et al. (2010). The BGPS is a 1.1 mm survey of dust emission in the Northern galactic plane, covering longitudes -10 < ... More
Using young massive star clusters to understand star formation and feedback in high-redshift-like environmentsJan 11 2016The formation environment of stars in massive stellar clusters is similar to the environment of stars forming in galaxies at a redshift of 1 - 3, at the peak star formation rate density of the Universe. As massive clusters are still forming at the present ... More
The Bolocam Galactic Plane Survey. XIII. Physical Properties and Mass Functions of Dense Molecular Cloud StructuresApr 06 2015We use the distance probability density function (DPDF) formalism of Ellsworth-Bowers et al. (2013, 2015) to derive physical properties for the collection of 1,710 Bolocam Galactic Plane Survey (BGPS) version 2 sources with well-constrained distance estimates. ... More
Beam Test Results for New Full-scale GEM Prototypes for a Future Upgrade of the CMS High-eta Muon SystemNov 16 2012The CMS GEM collaboration is considering Gas Electron Multipliers (GEMs) for upgrading the CMS forward muon system in the 1.5<|eta|<2.4 endcap region. GEM detectors can provide precision tracking and fast trigger information. They would improve the CMS ... More
G0.253+0.016: A centrally condensed, high-mass protoclusterMar 05 2014Despite their importance as stellar nurseries and the building blocks of galaxies, very little is known about the formation of the highest mass clusters. The dense clump G0.253+0.016 represents an example of a clump that may form an Arches-like, high-mass ... More
HST/ACS H-alpha Imaging of the Carina Nebula: Outflow Activity Traced by Irradiated Herbig-Haro JetsFeb 25 2010We report the discovery of new Herbig-Haro (HH) jets in the Carina Nebula, and we discuss the protostellar outflow activity of a young OB association. These are the first results of an HST/ACS H-alpha imaging survey of Carina. Adding to the one previously ... More
Integration by parts formula for locally smooth laws and applications to sensitivity computationsFeb 28 2007We consider random variables of the form $F=f(V_1,...,V_n)$, where $f$ is a smooth function and $V_i,i\in\mathbb{N}$, are random variables with absolutely continuous law $p_i(y) dy$. We assume that $p_i$, $i=1,...,n$, are piecewise differentiable and ... More
Construction and Performance of Large-Area Triple-GEM Prototypes for Future Upgrades of the CMS Forward Muon SystemNov 30 2011At present, part of the forward RPC muon system of the CMS detector at the CERN LHC remains uninstrumented in the high-\eta region. An international collaboration is investigating the possibility of covering the 1.6 < |\eta| < 2.4 region of the muon endcaps ... More
Absorption Filaments Towards the Massive Clump G0.253+0.016Sep 12 2014ALMA HCO+ observations of the infrared dark cloud G0.253+0.016 located in the Central Molecular Zone of the Galaxy are presented. The 89 GHz emission is area-filling, optically thick, and sub-thermally excited. Two types of filaments are seen in absorption ... More
Parsec-Scale Herbig-Haro Outflows from Intermediate Mass StarsNov 04 2003While there are many parsec-scale Herbig-Haro (HH) outflows known to be driven by low-mass young stars, few are associated with their intermediate mass counterparts. Here we present the discovery of five such bipolar outflows. Of these, LkHalpha 198, ... More
JCMT HARP CO 3-2 Observations of Molecular Outflows in W5Jun 07 2011Jul 20 2011New JCMT HARP CO 3-2 observations of the W5 star forming complex are presented, totaling an area of 12000 arcmin^2 with sensitivity better than 0.1 K per 0.4 km/s channel. We discovered 55 CO outflow candidates, of which 40 are associated with W5 and ... More
A new mid-infrared map of the BN/KL region using the Keck telescopeApr 06 2004We present a new mid-infrared (12.5micron) map of the BN/KL high-mass star-forming complex in Orion using the LWS instrument at Keck I. Despite poor weather we achieved nearly diffraction-limited images (FWHM = 0.38'') over a roughly 25'' X 25'' region ... More
The Orion fingers: Near-IR spectral imaging of an explosive outflowApr 15 2016We present near-IR (1.1-2.4 micron) position-position-velocity cubes of the 500-year-old Orion BN/KL explosive outflow with spatial resolution 1" and spectral resolution 86 km/s. We construct integrated intensity maps free of continuum sources of 15 H2 ... More
Non universality for the variance of the number of real roots of random trigonometric polynomialsNov 09 2017In this article, we consider the following family of random trigonometric polynomials $p_n(t,Y)=\sum_{k=1}^n Y_{k,1} \cos(kt)+Y_{k,2}\sin(kt)$ for a given sequence of i.i.d. random variables $\{Y_{k,1},Y_{k,2}\}_{k\ge 1}$ which are centered and standardized. ... More