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Determining the Galactic Mass Distribution Using Tidal Streams from Globular Clusters

Chigurupati Murali, John Dubinski
1999 Astronomical Journal  
We discuss how to use tidal streams from globular clusters to measure the mass distribution of the Milky Way.  ...  for stream stars; and another using a simple chi^2 estimator, which can be used when only projected positions and radial velocities are known for stream stars.  ...  What we describe is a procedure for fitting a projected tidal stream to the observational data using a χ 2 estimator.  ... 
doi:10.1086/300971 fatcat:6jbznv2p3zeu5c4tupuy3vii3q

GLOBULAR CLUSTER STREAMS AS GALACTIC HIGH-PRECISION SCALES—THE POSTER CHILD PALOMAR 5

Andreas H. W. Küpper, Eduardo Balbinot, Ana Bonaca, Kathryn V. Johnston, David W. Hogg, Pavel Kroupa, Basilio X. Santiago
2015 Astrophysical Journal  
Using the example of the tidal stream of the Milky Way globular cluster Palomar 5 (Pal 5), we demonstrate how observational data on streams can be efficiently reduced in dimensionality and modeled in a  ...  We also determine Pal 5's mass, distance and proper motion independently from other methods, which enables us to perform vital cross-checks.  ...  us understand the other mass estimates better.  ... 
doi:10.1088/0004-637x/803/2/80 fatcat:vb5vpbh27fetjb6llhfptzg3cy

THE PAL 5 STAR STREAM GAPS

R. G. Carlberg, C. J. Grillmair, Nathan Hetherington
2012 Astrophysical Journal  
We use the SDSS DR8 data to extend the density measurements of the trailing star stream to 23 degrees distance from the cluster, at which point the stream runs off the edge of the available sky coverage  ...  The statistical significance of a gap is estimated using bootstrap re-sampling of the control regions on either side of the stream.  ...  Adopting mean ages rather than end-point ages for the streams doubles the estimated gap rates and helps bring the data into agreement with the prediction.  ... 
doi:10.1088/0004-637x/760/1/75 fatcat:mm36mnli5vgbre6n3tkzylfheq

Galactic potential constraints from clustering in action space of combined stellar stream data [article]

Stella Reino, Elena M. Rossi, Robyn E. Sanderson, Elena Sellentin, Amina Helmi, Helmer H. Koppelman, Sanjib Sharma
2021 arXiv   pre-print
When including the Helmi stream in the data set, the mass uncertainty increases to M(< 20 kpc) = 3.12^+3.21_-0.46× 10^11 M_⊙.  ...  We find that we can only constrain the enclosed mass, and that the strongest constraints come from the GD-1, Pal 5 and Orphan streams whose combined data set yields M(< 20 kpc) = 2.96^+0.25_-0.26× 10^11M  ...  This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https:// www.cosmos.esa.int  ... 
arXiv:2007.00356v2 fatcat:n6qj553w2jauvabopxcthifgvy

Globular Cluster Streams as Galactic High-Precision Scales

Andreas H.W. Küpper, Eduardo Balbinot, Ana Bonaca, Kathryn V. Johnston, David W. Hogg, Pavel Kroupa, Basilio X. Santiago
2015 Proceedings of the International Astronomical Union  
With the example of Palomar 5, we demonstrate how modeling of a globular cluster stream allows us to simultaneously measure the properties of the disrupting globular cluster, its orbital motion, and the  ...  Tidal streams of globular clusters are ideal tracers of the Galactic gravitational potential.  ...  Mass estimates are accurate up to the uncertainties of globular cluster mass-to-light ratios, i.e., about a factor of two, (b) the simple stellar compositions of globular clusters, furthermore, allow for  ... 
doi:10.1017/s1743921315006742 fatcat:65tdqqmnlfg5xleuizkfskywjq

Dating the Tidal Disruption of Globular Clusters with GAIA Data on Their Stellar Streams

Sownak Bose, Idan Ginsburg, Abraham Loeb
2018 Astrophysical Journal Letters  
Here, we present a new technique for estimating the age of tidally disrupted globular cluster streams using the proper motions and parallaxes of tracer stars.  ...  The age can be deduced from astrometry using a modest number of stars, with the error on this estimate depending on the proximity of the stream and the number of tracer stars used.  ...  We are grateful to Long Wang for providing extensive support in the setup and use of Nbody6++, and to Adrian Jenkins for giving us access to his codes for generating cosmological initial conditions.  ... 
doi:10.3847/2041-8213/aac48c fatcat:jojnarosrbbpfdxjkrxriqbq3y

Galactic potential constraints from clustering in action space of combined stellar stream data

Stella Reino, Elena M Rossi, Robyn E Sanderson, Elena Sellentin, Amina Helmi, Helmer H Koppelman, Sanjib Sharma
2021 Monthly notices of the Royal Astronomical Society  
When including the Helmi stream in the data set, the mass uncertainty increases to $M(&lt; 20\ \mathrm{kpc}) = 3.12^{+3.21}_{-0.46} \times 10^{11} \ M_{\odot }$.  ...  We find that we can only constrain the enclosed mass, and that the strongest constraints come from the GD-1, Pal 5 and Orphan streams whose combined data set yields $M(&lt; 20\ \mathrm{kpc}) = 2.96^{+0.25  ...  Funding for A3 Palomar 5 stream data We use 2 literature sources to create a list of Palomar 5 stream members with a full 6D phase space map.  ... 
doi:10.1093/mnras/stab304 fatcat:4whzn22mmzdjhir42jy65dcwqa

MILKY WAY MASS AND POTENTIAL RECOVERY USING TIDAL STREAMS IN A REALISTIC HALO

Ana Bonaca, Marla Geha, Andreas H. W. Küpper, Jürg Diemand, Kathryn V. Johnston, David W. Hogg
2014 Astrophysical Journal  
Collectively, mass estimates using streams from our sample reach this fundamental limit, but individually they can be highly biased.  ...  We estimate that the assumption of a static and smooth dark matter potential in modeling of the GD-1 and Pal5-like streams introduces an error of up to 50% in the Milky Way mass estimates.  ...  This work has made use of the SuperMUC and zBox supercomputers at LRZ Garching, Germany and University of Zürich, Switzerland.  ... 
doi:10.1088/0004-637x/795/1/94 fatcat:mycagxmqrbfdzb54xyn7tcn7si

Divisive clustering of high dimensional data streams

David P. Hofmeyr, Nicos G. Pavlidis, Idris A. Eckley
2015 Statistics and computing  
Clustering streaming data is gaining importance as automatic data acquisition technologies are deployed in diverse applications.  ...  We propose a fully incremental projected divisive clustering method for high-dimensional data streams that is motivated by high density clustering.  ...  In Section 2 we discuss some existing data stream clustering algorithms.  ... 
doi:10.1007/s11222-015-9597-y fatcat:4cyk7tp3bzevjngzpr76zdx4fy

Stream–orbit misalignment – II. A new algorithm to constrain the Galactic potential

Jason L. Sanders, James Binney
2013 Monthly notices of the Royal Astronomical Society  
This approach is independent of the progenitor mass so is valid for all observed tidal streams.  ...  Motivated by the need for an improvement on orbit-fitting, we now present an algorithm for constraining the Galactic potential using tidal streams without assuming that streams delineate orbits.  ...  We also thank the anonymous referee for their useful suggestions which have improved the paper.  ... 
doi:10.1093/mnras/stt816 fatcat:a63rg7prifbajocw7rkhkqszwq

Packing fraction of clusters formed in free-falling granular streams based on flash X-ray radiography [article]

Yuuya Nagaashi, Akiko M. Nakamura, Sunao Hasegawa, Koji Wada
2021 arXiv   pre-print
We study the packing fraction of clusters in free-falling streams of spherical and irregularly shaped particles using flash X-ray radiography.  ...  The estimated packing fraction of clusters is low enough to correspond to coordination numbers less than 6.  ...  The stream of irregular particles showed rapid and easy cluster formation, which had a larger width than that of spherical particles.To estimate the packing fraction of the streams using Eq. (1-3), we  ... 
arXiv:2103.04017v2 fatcat:jjbvwfae7zfqtg7pbotj3xhw5u

VALIDITY OF HYDROSTATIC EQUILIBRIUM IN GALAXY CLUSTERS FROM COSMOLOGICAL HYDRODYNAMICAL SIMULATIONS

Daichi Suto, Hajime Kawahara, Tetsu Kitayama, Shin Sasaki, Yasushi Suto, Renyue Cen
2013 Astrophysical Journal  
We find that the mass estimated under the HSE assumption (the HSE mass) deviates from the true mass by up to ~ 30 %.  ...  We examine the validity of the hydrostatic equilibrium (HSE) assumption for galaxy clusters using one of the highest-resolution cosmological hydrodynamical simulations.  ...  We also thank Klaus Dolag for kindly providing us with SPH simulation data and calculating the gas acceleration, and Fujihiro Hamba for a useful comment on the interpretation of the inertial term in the  ... 
doi:10.1088/0004-637x/767/1/79 fatcat:njvvqvzft5cw3bdahwwz6svd3u

Uncovering fossils of the distant Milky Way with UNIONS: NGC 5466 and its stellar stream [article]

Jaclyn Jensen, Guillaume Thomas, Alan W. McConnachie, Else Starkenburg, Khyati Malhan, Julio Navarro, Nicolas Martin, Benoit Famaey, Rodrigo Ibata, Scott Chapman, Jean-Charles Cuillandre, Stephen Gwyn
2021 arXiv   pre-print
Using both BHBs and more numerous red giant branch stars cross-matched to Gaia Data Release 2, we identify extended tidal tails from NGC 5466 that are both spatially and kinematically coherent.  ...  Interestingly, we find that this stream does not follow the same path as the previous detection at large distances from the cluster.  ...  This work is based on data obtained as part of the Canada-France Imaging Survey (CFIS), a CFHT large program of the National Research Council of Canada and the French Centre National de la Recherche Scientifique  ... 
arXiv:2108.04340v1 fatcat:wwqoemrp6nfm3dzrra5kqrw3be

Estimate of the Mass and Radial Profile of the Orphan-Chenab Stream's Dwarf Galaxy Progenitor Using MilkyWay@home [article]

Eric J. Mendelsohn
2022 arXiv   pre-print
Within the progenitor's half-light radius, we estimate total a mass of (4.0±1.0)×10^5M_⊙.  ...  We optimize the evolution time, the baryonic and dark matter scale radii, and the baryonic and dark matter masses of the progenitor using a differential evolution algorithm.  ...  This implies that using a globular cluster for the mass estimate of a stellar system with a bluer peak color overestimates its mass.  ... 
arXiv:2201.03637v1 fatcat:pfij3nlkmva2nlqj6ociguuabi

Estimating the ages of open star clusters from properties of their extended tidal tails [article]

František Dinnbier, Pavel Kroupa, Ladislav Šubr, Tereza Jeřábková
2021 arXiv   pre-print
Since at a given Galactocentric radius, β is only a function of age t regardless of the initial properties of the cluster, we estimate the cluster age by inverting the analytical formula β = β (t).  ...  as the cluster (i.e. being coeval with the cluster), we derive the analytical formula for the tilt angle β between the long axis of the tidal tail and the orbital direction for clusters or streams on  ...  We attempted to use the same analytical approach for estimating the initial mass of the clusters from the width of the tidal structure, but this yielded substantially lower masses than the masses of the  ... 
arXiv:2112.03940v1 fatcat:prcaqhy3nvhgjedy72flmwatam
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