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MAORY science cases white book [article]

G. Fiorentino , S. Douté, M. Mapelli IPAG,
2019 arXiv   pre-print
Here we present a first collection of science cases for MAORY feeding the E-ELT first light camera and spectrograph MICADO.  ...  Since the general science cases for E-ELT have already been developed elsewhere, here we focus on the design of specific observations, to explore the capabilities and observing modes of the system.  ...  Studying their structure and shape. Brief description of science case: The first galaxies are thought to have formed in the first 300-400 Myr since the Big Bang.  ... 
arXiv:1712.04222v2 fatcat:q7tsmqlj7nc2zdpdvbagax4xaa

Gaussian Mixture Models Use-Case

Ryan Maas, Jeremy Hyrkas, Olivia Grace Telford, Magdalena Balazinska, Andrew Connolly, Bill Howe
2015 Proceedings of the 3rd VLDB Workshop on In-Memory Data Mangement and Analytics - IMDM '15  
In our work with scientists, we find that Gaussian Mixture Modeling is a common type of analysis applied to increasingly large datasets.  ...  We implement this algorithm in the Myria shared-nothing relational data management system, which performs the computation in memory.  ...  Acknowledgments This work is supported in part by NSF IGERT grant DGE-1258485, NSF grant IIS-1247469, the Intel Science and Technology Center for Big Data, and a gift from Amazon.  ... 
doi:10.1145/2803140.2803143 dblp:conf/vldb/MaasHTBCH15 fatcat:5rjztipg4nhjnmontsoisk7i3y

Witnessing galaxy preprocessing in the local Universe: the case of a star-bursting group falling into Abell 1367

L. Cortese, G. Gavazzi, A. Boselli, P. Franzetti, R. C. Kennicutt, K. O'Neil, S. Sakai
2006 Astronomy and Astrophysics  
Peculiar morphologies and unusually high Halpha emission are associated with two giant galaxies and at least ten dwarfs/extragalactic HII regions, making this group the region with the highest density  ...  of star formation activity ever observed in the local clusters.  ...  This research has made use of the GOLDMine Database, operated by the Universitá degli Studi di Milano-Bicocca.  ... 
doi:10.1051/0004-6361:20064873 fatcat:q2di2ozzunfjfj7rettdpg2huu

Thirty Meter Telescope Detailed Science Case: 2015

Warren Skidmore
2015 Research in Astronomy and Astrophysics  
The TMT Detailed Science Case describes the transformational science that the Thirty Meter Telescope will enable.  ...  More than 150 astronomers from within the TMT partnership and beyond offered input in compiling the new 2015 Detailed Science Case.  ...  Those data can show if clusters are expanding or contracting.  ... 
doi:10.1088/1674-4527/15/12/001 fatcat:4oipwdf675acffvw34lmzxh254

ANOMALOUS MICROWAVE EMISSION IN H ii REGIONS: IS IT REALLY ANOMALOUS? THE CASE OF RCW 49

Roberta Paladini, Adriano Ingallinera, Claudia Agliozzo, Christopher T. Tibbs, Alberto Noriega-Crespo, Grazia Umana, Clive Dickinson, Corrado Trigilio
2015 Astrophysical Journal  
Here, we investigate the case of RCW 49, for which the Cosmic Background Imager tentatively ( 3 sigma) detected Anomalous Microwave Emission at 31 GHz on angular scales of 7'.  ...  The detection of an excess of emission at microwave frequencies with respect to the predicted free-free emission has been reported for several Galactic HII regions.  ...  of star formation, possibly triggered by the stellar winds and shocks associated with the Wd2 cluster (Whitney et al. 2004) .  ... 
doi:10.1088/0004-637x/813/1/24 fatcat:hrq5i334zjcahf3utk4sqt3n7u

WHAT DRIVES THE EXPANSION OF GIANT H II REGIONS?: A STUDY OF STELLAR FEEDBACK IN 30 DORADUS

Laura A. Lopez, Mark R. Krumholz, Alberto D. Bolatto, J. Xavier Prochaska, Enrico Ramirez-Ruiz
2011 Astrophysical Journal  
The mechanism of this stellar feedback is debated theoretically: possible sources of pressure include the classical warm HII gas, the hot gas generated by shock-heating from stellar winds and supernovae  ...  We find that radiation pressure dominates within 75 pc of the central star cluster, R136, while the HII gas pressure dominates at larger radii.  ...  In particular, the former case has large P dir close to the star cluster and a decline in P dir with distance from the center.  ... 
doi:10.1088/0004-637x/731/2/91 fatcat:7s5buntkura4hkq7h7rl3tcj6i

Multiwavelength Search and Studies of Active Galaxies and Quasars

Areg Mickaelian
2017 Communications of the Byurakan Astrophysical Observatory  
These projects since late 1980s were focused on multiwavelength search and studies of AGN and Starbursts (SB). 1103 blue stellar objects (BSOs) on the basis of their UV-excess were selected using Markarian  ...  with Spitzer. 2791 ROSAT FSC sources were optically identified using Hamburg Quasar Survey (HQS) lowdispersion spectra and many AGN were discovered by follow-up observations.  ...  Brighter objects are normal bright galaxies, while we believe that all faint ones are candidate AGN with some contamination of distant clusters.  ... 
doi:10.52526/25792776-2017.1-15 fatcat:oxvagbvyl5dcfdzb4vbmjhmypu

A detailed study of the L1641N star formation region

M. Gålfalk, G. Olofsson
2008 Astronomy and Astrophysics  
We search for young stellar objects (YSOs) in the L1641N cluster and characterize the star formation activity through determination of the age distribution, mass function, spatial distribution, and the  ...  More than 50 of the brightest I-band sources were then studied with follow-up optical spectroscopy (5780−8340 Å) to check for signs of accretion (Hα in emission) and youth (Li I λ6707 in absorption) and  ...  The authors would like to thank Peter Hauschildt for providing us with the dwarf model spectra we used in our classifications.  ... 
doi:10.1051/0004-6361:20079176 fatcat:omqb6agb7rebtf47c3xnl2p544

AChandraX-ray study of the young star cluster NGC 6231: low-mass population and initial mass function

F. Damiani, G. Micela, S. Sciortino
2016 Astronomy and Astrophysics  
We also find strong Halpha emission in 9% of cluster PMS stars. The dependence of X-ray properties on mass, stellar structure, and age agrees with extrapolations based on other young clusters.  ...  We use X-ray data, complemented by optical/IR data, to establish cluster membership.  ...  This work was also using data products from observations made with ESO Telescopes A82, page 20 of 26 F.  ... 
doi:10.1051/0004-6361/201629029 fatcat:6iywejdczree5k6v53yvq4uprq

Science Case for the Einstein Telescope [article]

Michele Maggiore, Chris van den Broeck, Nicola Bartolo, Enis Belgacem, Daniele Bertacca, Marie Anne Bizouard, Marica Branchesi, Sebastien Clesse, Stefano Foffa, Juan García-Bellido, Stefan Grimm, Jan Harms, Tanja Hinderer, Sabino Matarrese (+4 others)
2020 arXiv   pre-print
ET will explore the universe with gravitational waves up to cosmological distances.  ...  SNR signals compared to current EM observations from these early times. 2 ET will uncover the full population of coalescing stellar and intermediate mass BHs in the Universe, over the whole epoch since  ...  Schematically, we can identify the following main items as part of the ET science case: • Astrophysics -Black hole properties: origin (stellar vs. primordial), evolution, demography.  ... 
arXiv:1912.02622v4 fatcat:xsp6cfz6dfbutc7k3bzyd55nu4

UV bright red-sequence galaxies: a comparative study between UV upturn and UV weak systems [article]

M. L. L. Dantas
2020 arXiv   pre-print
Ultraviolet (UV) emission from galaxies is associated with hot components, whether from stellar sources or not.  ...  By stratifying the sample into emission line classes, the galaxies classified as retired/passive -- the ones associated with evolved stellar phases -- dominate the behaviour with z and logM*.  ...  It is the so-called era of big data.  ... 
arXiv:2011.06476v1 fatcat:lllfsicosvhqpmf6fneakxlysy

A comprehensive study of NGC 2023 with XMM-Newton and Spitzer

M. A. Lopez-Garcia, J. Lopez-Santiago, J. F. Albacete-Colombo, P. G. Perez-Gonzalez, E. de Castro
2012 Monthly notices of the Royal Astronomical Society  
Nearby star-forming regions are ideal laboratories to study high-energy emission of different stellar populations, from very massive stars to brown dwarfs.  ...  We combine optical and infrared data to determine physical properties (mass, temperature, luminosity, presence of accretion disks) of the stars detected in an XMM-Newton observation.  ...  X-RAY OBSERVATION AND DATA REDUCTION The XMM-Newton observation of the NGC 2023 reflection nebula (ID 0112640201) was part of an observing program aimed at studying deeply embedded stellar clusters in  ... 
doi:10.1093/mnras/sts373 fatcat:v3eosbrggfdolhht7masvp4nke

A detailed study of the L1641N star formation region [article]

M.Gaalfalk, G.Olofsson
2008 arXiv   pre-print
We search for young stellar objects (YSOs) in the L1641N cluster and characterize the star formation activity through determination of the age distribution, mass function, spatial distribution, and the  ...  of an increased star formation rate with time.  ...  The authors would like to thank Peter Hauschildt for providing us with the dwarf model spectra we used in our classifications.  ... 
arXiv:0805.3077v1 fatcat:oxktjacczrfcnnrhimis7vkvza

DISRUPTION OF A RED GIANT STAR BY A SUPERMASSIVE BLACK HOLE AND THE CASE OF PS1-10jh

Tamara Bogdanović, Roseanne M. Cheng, Pau Amaro-Seoane
2014 Astrophysical Journal  
Motivated by this discovery and in anticipation of others, we consider tidal interaction of an RG star with a supermassive black hole (SMBH) which leads to the stripping of the stellar envelope and subsequent  ...  In the case of tidal disruption candidate PS1-10jh we find that there is a set of orbital solutions at high eccentricities in which the tidally stripped hydrogen envelope is accreted by the SMBH before  ...  These studies indicate that the probability that an RG star will encounter a stellar mass black hole (or with a lesser probability a main sequence star) at least once during its lifetime is substantial  ... 
doi:10.1088/0004-637x/788/2/99 fatcat:w6zxe4sjevfbhchmkxqsv7kd6q

The case for primordial black holes as dark matter

M. R. S. Hawkins
2011 Monthly notices of the Royal Astronomical Society  
In all these cases, the observations are found to be consistent with the predictions for microlensing by a population of stellar mass compact bodies.  ...  The aim of this paper is to present the case that stellar mass primordial black holes make up the dark matter component of the Universe.  ...  Data are available online through the SuperCOSMOS Science Archive: http://surveys.roe.ac.uk/ssa  ... 
doi:10.1111/j.1365-2966.2011.18890.x fatcat:g5muepeirbcspcazlqbeucyjqa
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