H. Bhatt - WASA-at-COSY Collaboration

H. Bhatt
Are you H. Bhatt?

Claim your profile, edit publications, add additional information:

Contact Details

Name
H. Bhatt
Affiliation
WASA-at-COSY Collaboration
Location

Pubs By Year

External Links

Pub Categories

 
Nuclear Experiment (22)
 
Astrophysics of Galaxies (17)
 
High Energy Physics - Experiment (11)
 
Solar and Stellar Astrophysics (10)
 
High Energy Astrophysical Phenomena (7)
 
Instrumentation and Methods for Astrophysics (2)
 
High Energy Physics - Phenomenology (2)
 
Computer Science - Computation and Language (1)
 
Physics - Materials Science (1)

Publications Authored By H. Bhatt

Exclusive measurements of the quasi-free $pn \to pp\pi^-$ and $pp \to pp\pi^0$ reactions have been performed by means of $pd$ collisions at $T_p$ = 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $T_p = 0. Read More

Deep optical photometric data on the NGC 7538 region were collected and combined with archival data sets from $Chandra$, 2MASS and {\it Spitzer} surveys in order to generate a new catalog of young stellar objects (YSOs) including those not showing IR excess emission. This new catalog is complete down to 0.8 M$_\odot$. Read More

The search for 4He-eta bound states was performed with the WASA-at-COSY facility via the measurement of the excitation function for the dd->3He n pi0 and dd->3He p pi- processes. The beam momentum was varied continuously between 2.127 GeV/c and 2. Read More

Using the production reactions $pd\to {}^3\mbox{He}\,\omega$ and $pp\to pp\omega$, the Dalitz plot distribution for the $\omega \to \pi^+ \pi^- \pi^0$ decay is studied with the WASA detector at COSY, based on a combined data sample of $ (4.408\pm 0.042) \times 10^4$ events. Read More

Automatic short answer grading (ASAG) techniques are designed to automatically assess short answers to questions in natural language, having a length of a few words to a few sentences. Supervised ASAG techniques have been demonstrated to be effective but suffer from a couple of key practical limitations. They are greatly reliant on instructor provided model answers and need labeled training data in the form of graded student answers for every assessment task. Read More

We propose to measure the photo-production cross section of $J/{\psi}$ near threshold, in search of the recently observed LHCb hidden-charm resonances $P_c$(4380) and $P_c$(4450) consistent with 'pentaquarks'. The observation of these resonances in photo-production will provide strong evidence of the true resonance nature of the LHCb states, distinguishing them from kinematic enhancements. A bremsstrahlung photon beam produced with an 11 GeV electron beam at CEBAF covers the energy range of $J/{\psi}$ production from the threshold photo-production energy of 8. Read More

The optical spectra of Seyfert galaxies are often dominated by emission lines excited by both star formation and AGN activity. Standard calibrations (such as for the star formation rate) are not applicable to such composite (mixed) spectra. In this paper, we describe how integral field data can be used to spectrally and spatially separate emission associated with star formation from emission associated with accretion onto an active galactic nucleus (AGN). Read More

Various theoretical calculations based on QCD or hadronic interactions predict that in addition to the recently observed dibaryon resonance $d^*(2380)$ with $I(J^P) = 0(3^+)$ there should also exist a dibaryon resonance with mirrored quantum numbers $I(J^P) = 3(0^+)$. We report here on a search for such a $NN$-decoupled state in data on the $pp \to pp\pi^+\pi^+\pi^-\pi^-$ reaction. Since no clear-cut evidence has been found, we give upper limits for the production cross section of such a resonance in the mass range 2280 - 2500 MeV. Read More

2016May
Authors: Alan McConnachie, Carine Babusiaux, Michael Balogh, Simon Driver, Pat Côté, Helene Courtois, Luke Davies, Laura Ferrarese, Sarah Gallagher, Rodrigo Ibata, Nicolas Martin, Aaron Robotham, Kim Venn, Eva Villaver, Jo Bovy, Alessandro Boselli, Matthew Colless, Johan Comparat, Kelly Denny, Pierre-Alain Duc, Sara Ellison, Richard de Grijs, Mirian Fernandez-Lorenzo, Ken Freeman, Raja Guhathakurta, Patrick Hall, Andrew Hopkins, Mike Hudson, Andrew Johnson, Nick Kaiser, Jun Koda, Iraklis Konstantopoulos, George Koshy, Khee-Gan Lee, Adi Nusser, Anna Pancoast, Eric Peng, Celine Peroux, Patrick Petitjean, Christophe Pichon, Bianca Poggianti, Carlo Schmid, Prajval Shastri, Yue Shen, Chris Willot, Scott Croom, Rosine Lallement, Carlo Schimd, Dan Smith, Matthew Walker, Jon Willis, Alessandro Bosselli Matthew Colless, Aruna Goswami, Matt Jarvis, Eric Jullo, Jean-Paul Kneib, Iraklis Konstantopoloulous, Jeff Newman, Johan Richard, Firoza Sutaria, Edwar Taylor, Ludovic van Waerbeke, Giuseppina Battaglia, Pat Hall, Misha Haywood, Charli Sakari, Carlo Schmid, Arnaud Seibert, Sivarani Thirupathi, Yuting Wang, Yiping Wang, Ferdinand Babas, Steve Bauman, Elisabetta Caffau, Mary Beth Laychak, David Crampton, Daniel Devost, Nicolas Flagey, Zhanwen Han, Clare Higgs, Vanessa Hill, Kevin Ho, Sidik Isani, Shan Mignot, Rick Murowinski, Gajendra Pandey, Derrick Salmon, Arnaud Siebert, Doug Simons, Else Starkenburg, Kei Szeto, Brent Tully, Tom Vermeulen, Kanoa Withington, Nobuo Arimoto, Martin Asplund, Herve Aussel, Michele Bannister, Harish Bhatt, SS Bhargavi, John Blakeslee, Joss Bland-Hawthorn, James Bullock, Denis Burgarella, Tzu-Ching Chang, Andrew Cole, Jeff Cooke, Andrew Cooper, Paola Di Matteo, Ginevra Favole, Hector Flores, Bryan Gaensler, Peter Garnavich, Karoline Gilbert, Rosa Gonzalez-Delgado, Puragra Guhathakurta, Guenther Hasinger, Falk Herwig, Narae Hwang, Pascale Jablonka, Matthew Jarvis, Umanath Kamath, Lisa Kewley, Damien Le Borgne, Geraint Lewis, Robert Lupton, Sarah Martell, Mario Mateo, Olga Mena, David Nataf, Jeffrey Newman, Enrique Pérez, Francisco Prada, Mathieu Puech, Alejandra Recio-Blanco, Annie Robin, Will Saunders, Daniel Smith, C. S. Stalin, Charling Tao, Karun Thanjuvur, Laurence Tresse, Ludo van Waerbeke, Jian-Min Wang, David Yong, Gongbo Zhao, Patrick Boisse, James Bolton, Piercarlo Bonifacio, Francois Bouchy, Len Cowie, Katia Cunha, Magali Deleuil, Ernst de Mooij, Patrick Dufour, Sebastien Foucaud, Karl Glazebrook, John Hutchings, Chiaki Kobayashi, Rolf-Peter Kudritzki, Yang-Shyang Li, Lihwai Lin, Yen-Ting Lin, Martin Makler, Norio Narita, Changbom Park, Ryan Ransom, Swara Ravindranath, Bacham Eswar Reddy, Marcin Sawicki, Luc Simard, Raghunathan Srianand, Thaisa Storchi-Bergmann, Keiichi Umetsu, Ting-Gui Wang, Jong-Hak Woo, Xue-Bing Wu

MSE is an 11.25m aperture observatory with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. Read More

We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-AGN mixing curves on standard emission line diagnostic diagrams which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ~ 0). Read More

We report on a high-statistics measurement of the most basic double pionic fusion reaction $\vec{n}p \to d\pi^0\pi^0$ over the energy region of the $d^*(2380)$ resonance by use of a polarized deuteron beam and observing the double fusion reaction in the quasifree scattering mode. The measurements were performed with the WASA detector setup at COSY. The data reveal substantial analyzing powers and confirm conclusions about the $d^*$ resonance obtained from unpolarized measurements. Read More

The WASA-at-COSY experiment has collected $3\times10^{7}$ events with $\eta$-mesons produced via the reaction $pd\rightarrow{^{3}\textrm{He}}\eta$ at $\textrm{T} = 1.0 \textrm{GeV}$. Using this data set, we evaluate the branching ratios of the decays $\eta\to\pi^{+}\pi^{-}\gamma$, $\eta\to e^{+}e^{-}\gamma$, $\eta\to\pi^{+}\pi^{-}e^{+}e^{-}$ and $\eta\to e^{+}e^{-}e^{+}e^{-}$. Read More

We report here the evidences of hydrogen bond symmetrization in the simplest amino acid- carboxylic acid complex, glycinium oxalate, at moderate pressures of 8 GPa using in-situ infrared and Raman spectroscopic investigations combined with first-principles simulations. The protonation of the semioxalate units through dynamic proton movement results in infinite oxalate chains. At pressures above 12 GPa, the glycine units systematically reorient with pressure to form hydrogen bonded supramolecular assemblies held together by these chains. Read More

The Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) is a targeted survey probing the narrow-line regions (NLRs) of a representative sample of ~140 nearby (z<0.02) Seyfert galaxies by means of optical integral field spectroscopy. The survey is based on a homogeneous data set observed using the Wide Field Spectrograph WiFeS. Read More

We present Wide Field Spectrograph (WiFeS) integral field spectroscopy and HST FOS spectroscopy for the LINER galaxy NGC 1052. We infer the presence of a turbulent accretion flow forming a small-scale accretion disk. We find a large-scale outflow and ionisation cone along the minor axis of the galaxy. Read More

Here we describe the \emph{Siding Spring Southern Seyfert Spectroscopic Snapshot Survey} (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph (WiFeS) mounted on the ANU 2.3m telescope located at the Siding Spring Observatory to deliver an integral field of $38\times25$~ arcsec at a spectral resolution of $R=7000$ in the red ($530-710$nm), and $R=3000$ in the blue ($340-560$nm). Read More

In this paper, we present results of TeV $\gamma$--ray observations of the high synchrotron peaked BL Lac object 1ES 1218+304 (z=0.182) with the $TACTIC$ (TeV Atmospheric Cherenkov Telescope with Imaging Camera). The observations are primarily motivated by the unusually hard GeV-TeV spectrum of the source despite its relatively large redshift. Read More

Exclusive measurements of the quasi-free $np \to np\pi^0\pi^0$ reaction have been performed by means of $dp$ collisions at $T_d$ = 2.27 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $\sqrt s$ = (2. Read More

Exclusive and kinematically complete measurements of the double pionic fusion to $^3$He have been performed in the energy region of the so-called ABC effect, which denotes a pronounced low-mass enhancement in the $\pi\pi$-invariant mass spectrum. The experiments were carried out with the WASA detector setup at COSY. Similar to the observations in the basic $pn \to d \pi^0\pi^0$ reaction and in the $dd \to ^4$He$\pi^0\pi^0$ reaction, the data reveal a correlation between the ABC effect and a resonance-like energy dependence in the total cross section. Read More

2014Aug
Authors: P. Adlarson1, W. Augustyniak2, W. Bardan3, M. Bashkanov4, F. S. Bergmann5, M. Berłowski6, H. Bhatt7, M. Büscher8, H. Calén9, I. Ciepał10, H. Clement11, D. Coderre12, E. Czerwiński13, K. Demmich14, E. Doroshkevich15, R. Engels16, A. Erven17, W. Erven18, W. Eyrich19, P. Fedorets20, K. Föhl21, K. Fransson22, F. Goldenbaum23, P. Goslawski24, A. Goswami25, K. Grigoryev26, C. --O. Gullström27, F. Hauenstein28, L. Heijkenskjöld29, V. Hejny30, M. Hodana31, B. Höistad32, N. Hüsken33, A. Jany34, B. R. Jany35, L. Jarczyk36, T. Johansson37, B. Kamys38, G. Kemmerling39, F. A. Khan40, A. Khoukaz41, D. A. Kirillov42, S. Kistryn43, H. Kleines44, B. Kłos45, M. Krapp46, W. Krzemień47, P. Kulessa48, A. Kupść49, K. Lalwani50, D. Lersch51, B. Lorentz52, A. Magiera53, R. Maier54, P. Marciniewski55, B. Mariański56, M. Mikirtychiants57, H. --P. Morsch58, P. Moskal59, H. Ohm60, I. Ozerianska61, E. Perez del Rio62, N. M. Piskunov63, P. Podkopał64, D. Prasuhn65, A. Pricking66, D. Pszczel67, K. Pysz68, A. Pyszniak69, C. F. Redmer70, J. Ritman71, A. Roy72, Z. Rudy73, S. Sawant74, S. Schadmand75, T. Sefzick76, V. Serdyuk77, R. Siudak78, T. Skorodko79, M. Skurzok80, J. Smyrski81, V. Sopov82, R. Stassen83, J. Stepaniak84, E. Stephan85, G. Sterzenbach86, H. Stockhorst87, H. Ströher88, A. Szczurek89, A. Täschner90, A. Trzciński91, R. Varma92, G. J. Wagner93, M. Wolke94, A. Wrońska95, P. Wüstner96, P. Wurm97, A. Yamamoto98, L. Yurev99, J. Zabierowski100, M. J. Zieliński101, A. Zink102, J. Złomańczuk103, P. {Ż}uprański104, M. {Ż}urek105, R. L. Workman106, W. J. Briscoe107, I. I. Strakovsky108
Affiliations: 1WASA-at-COSY Collaboration, 2WASA-at-COSY Collaboration, 3WASA-at-COSY Collaboration, 4WASA-at-COSY Collaboration, 5WASA-at-COSY Collaboration, 6WASA-at-COSY Collaboration, 7WASA-at-COSY Collaboration, 8WASA-at-COSY Collaboration, 9WASA-at-COSY Collaboration, 10WASA-at-COSY Collaboration, 11WASA-at-COSY Collaboration, 12WASA-at-COSY Collaboration, 13WASA-at-COSY Collaboration, 14WASA-at-COSY Collaboration, 15WASA-at-COSY Collaboration, 16WASA-at-COSY Collaboration, 17WASA-at-COSY Collaboration, 18WASA-at-COSY Collaboration, 19WASA-at-COSY Collaboration, 20WASA-at-COSY Collaboration, 21WASA-at-COSY Collaboration, 22WASA-at-COSY Collaboration, 23WASA-at-COSY Collaboration, 24WASA-at-COSY Collaboration, 25WASA-at-COSY Collaboration, 26WASA-at-COSY Collaboration, 27WASA-at-COSY Collaboration, 28WASA-at-COSY Collaboration, 29WASA-at-COSY Collaboration, 30WASA-at-COSY Collaboration, 31WASA-at-COSY Collaboration, 32WASA-at-COSY Collaboration, 33WASA-at-COSY Collaboration, 34WASA-at-COSY Collaboration, 35WASA-at-COSY Collaboration, 36WASA-at-COSY Collaboration, 37WASA-at-COSY Collaboration, 38WASA-at-COSY Collaboration, 39WASA-at-COSY Collaboration, 40WASA-at-COSY Collaboration, 41WASA-at-COSY Collaboration, 42WASA-at-COSY Collaboration, 43WASA-at-COSY Collaboration, 44WASA-at-COSY Collaboration, 45WASA-at-COSY Collaboration, 46WASA-at-COSY Collaboration, 47WASA-at-COSY Collaboration, 48WASA-at-COSY Collaboration, 49WASA-at-COSY Collaboration, 50WASA-at-COSY Collaboration, 51WASA-at-COSY Collaboration, 52WASA-at-COSY Collaboration, 53WASA-at-COSY Collaboration, 54WASA-at-COSY Collaboration, 55WASA-at-COSY Collaboration, 56WASA-at-COSY Collaboration, 57WASA-at-COSY Collaboration, 58WASA-at-COSY Collaboration, 59WASA-at-COSY Collaboration, 60WASA-at-COSY Collaboration, 61WASA-at-COSY Collaboration, 62WASA-at-COSY Collaboration, 63WASA-at-COSY Collaboration, 64WASA-at-COSY Collaboration, 65WASA-at-COSY Collaboration, 66WASA-at-COSY Collaboration, 67WASA-at-COSY Collaboration, 68WASA-at-COSY Collaboration, 69WASA-at-COSY Collaboration, 70WASA-at-COSY Collaboration, 71WASA-at-COSY Collaboration, 72WASA-at-COSY Collaboration, 73WASA-at-COSY Collaboration, 74WASA-at-COSY Collaboration, 75WASA-at-COSY Collaboration, 76WASA-at-COSY Collaboration, 77WASA-at-COSY Collaboration, 78WASA-at-COSY Collaboration, 79WASA-at-COSY Collaboration, 80WASA-at-COSY Collaboration, 81WASA-at-COSY Collaboration, 82WASA-at-COSY Collaboration, 83WASA-at-COSY Collaboration, 84WASA-at-COSY Collaboration, 85WASA-at-COSY Collaboration, 86WASA-at-COSY Collaboration, 87WASA-at-COSY Collaboration, 88WASA-at-COSY Collaboration, 89WASA-at-COSY Collaboration, 90WASA-at-COSY Collaboration, 91WASA-at-COSY Collaboration, 92WASA-at-COSY Collaboration, 93WASA-at-COSY Collaboration, 94WASA-at-COSY Collaboration, 95WASA-at-COSY Collaboration, 96WASA-at-COSY Collaboration, 97WASA-at-COSY Collaboration, 98WASA-at-COSY Collaboration, 99WASA-at-COSY Collaboration, 100WASA-at-COSY Collaboration, 101WASA-at-COSY Collaboration, 102WASA-at-COSY Collaboration, 103WASA-at-COSY Collaboration, 104WASA-at-COSY Collaboration, 105WASA-at-COSY Collaboration, 106SAID Data Analysis Center, 107SAID Data Analysis Center, 108SAID Data Analysis Center

New data on quasifree polarized neutron-proton scattering, in the region of the recently observed $d^*$ resonance structure, have been obtained by exclusive and kinematically complete high-statistics measurements with WASA at COSY. This paper details the determination of the beam polarization, checks of the quasifree character of the scattering process, on all obtained $A_y$ angular distributions and on the new partial-wave analysis, which includes the new data producing a resonance pole in the $^3D_3$-$^3G_3$ coupled partial waves at ($2380\pm10 - i40\pm5$) MeV -- in accordance with the $d^*$ dibaryon resonance hypothesis. The effect of the new partial-wave solution on the description of total and differential cross section data as well as specific combinations of spin-correlation and spin-transfer observables available from COSY-ANKE measurements at $T_d$ = 2. Read More

Here we present the first results from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) which aims to investigate the physics of ~140 radio-detected southern active Galaxies with z<0.02 through Integral Field Spectroscopy using the Wide Field Spectrograph (WiFeS). This instrument provides data cubes of the central 38 x 25 arc sec. Read More

We report an X-ray flare from 3XMM J014528.9+610729, serendipitously detected during the observation of the open star cluster NGC 663. The colour-colour space technique using optical and infrared data reveals the X-ray source as a candidate spiral galaxy. Read More

Charge symmetry breaking (CSB) observables are a suitable experimental tool to examine effects induced by quark masses on the nuclear level. Previous high precision data from TRIUMF and IUCF are currently used to develop a consistent description of CSB within the framework of chiral perturbation theory. In this work the experimental studies on the reaction dd->4He{\pi}0 have been extended towards higher excess energies in order to provide information on the contribution of p-waves in the final state. Read More

2014Jun

Dalitz plot distribution of the $\eta\to\pi^+\pi^-\pi^0$ decay is determined using a data sample of $1.2\cdot 10^7$ $\eta$ mesons from $pd\to ^3\textrm{He}\eta$ reaction at 1 GeV collected by the WASA detector at COSY. Read More

Exclusive and kinematically complete high-statistics measurements of quasifree polarized $\vec{n}p$ scattering have been performed in the energy region of the narrow resonance structure $d^*$ with $I(J^P) = 0(3^+)$, $M \approx$ 2380 MeV/$c^2$ and $\Gamma \approx$ 70 MeV observed recently in the double-pionic fusion channels $pn \to d\pi^0\pi^0$ and $pn \to d\pi^+\pi^-$. The experiment was carried out with the WASA detector setup at COSY having a polarized deuteron beam impinged on the hydrogen pellet target and utilizing the quasifree process $\vec{d}p \to np + p_{spectator}$. That way the $np$ analyzing power $A_y$ was measured over a large angular range. Read More

2014Feb

We present new data for angular distributions and on the cross section ratio of the p + d -> 3He + eta reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. Read More

2013Dec
Affiliations: 1Astrophysical Sciences Division, Bhabha Atomic Research Center, 2Aryabhatta Research Institute of Observational Sciences, 3Tata Institute of Fundamental Research, 4Aryabhatta Research Institute of Observational Sciences, 5Aryabhatta Research Institute of Observational Sciences

We present an analysis of seven intense X-ray flares observed from six stars (LAV 796, LAV 1174, SHM2002 3734, 2MASS 02191082+5707324, V553 Car, V557 Car) for the first time. These stars are located in the region of young open star clusters NGC 869 and IC 2602. These flares detected in the XMM-Newton data show a rapid rise (10-40 minutes) and a slow decay (20-90 minutes). Read More

2013Nov
Affiliations: 1Astrophysical Sciences Division, Bhabha Atomic Research Center, 2Aryabhatta Research Institute of Observational Sciences, 3Tata Institute of Fundamental Research, 4Aryabhatta Research Institute of Observational Sciences, 5Aryabhatta Research Institute of Observational Sciences

We present a detailed investigation of X-ray source contents of eight young open clusters with ages between 4 to 46 Myr using archival X-ray data from XMM-Newton. The probable cluster memberships of the X-ray sources have been established on the basis of multi-wavelength archival data, and samples of 152 pre-main sequence (PMS) low mass (< 2 M_\odot), 36 intermediate mass (2 - 10 M_\odot) and 16 massive (> 10 M_\odot) stars have been generated. X-ray spectral analyses of high mass stars reveal the presence of high temperature plasma with temperature <2 keV, and mean L_X/L_{bol} of 10^{-6. Read More

2013Jun

Exclusive measurements of the quasi-free $pn \to pp\pi^0\pi^-$ reaction have been performed by means of $pd$ collisions at $T_p$ = 1.2 GeV using the WASA detector setup at COSY. Total and differential cross sections have been obtained covering the energy region $\sqrt s$ = (2. Read More

We wish to map the magnetic field geometry and to study the dust properties of the starless cloud, L1570, using multi-wavelength optical polarimetry and photometry of the stars projected on the cloud. We made R-band imaging polarimetry of the stars projected on a cloud, L1570, to trace the magnetic field orientation. We also made multi-wavelength polarimetric and photometric observations to constrain the properties of dust in L1570. Read More

2013Apr

An exclusive measurement of the dd -> 3He n \pi 0 reaction was carried at a beam momentum of p = 1.2 GeV/c using the WASA-at-COSY facility. For the first time data on the total cross section as well as differential distributions were obtained. Read More

We present results of our $R-$band polarimetry of a cometary globule, LBN 437 (Gal96-15, $\ell$ $=$ 96$\degree$, \textit{b} $=-15\degree$), to study magnetic field geometry of the cloud. We estimated a distance of $360\pm65$ pc to LBN 437 (also one additional cloud, CB 238) using near-IR photometric method. Foreground contribution to the observed polarisation values was subtracted by making polarimetric observations of stars that are located in the direction of the cloud and with known distances from the Hipparcos parallax measurements. Read More

2013Apr

The presently world largest data sample of pi0 --> gamma e+e- decays containing nearly 5E5 events was collected using the WASA detector at COSY. A search for a dark photon U produced in the pi0 --> gamma U --> gamma e+e- decay from the pp-->pp\pi^0 reaction was carried out. An upper limit on the square of the U-gamma mixing strength parameter epsilon^2 of 5e-6 at 90% CL was obtained for the mass range 20 MeV Read More

We analysed the archival XMM-Newton data of the radio loud narrow line Seyfert1 galaxy PMN J0948+0022 in the energy range 0.3--10.0 keV. Read More

2013Jan
Authors: P. Adlarson1, W. Augustyniak2, W. Bardan3, M. Bashkanov4, T. Bednarski5, F. S. Bergmann6, M. Berlowski7, H. Bhatt8, M. Buescher9, H. Calen10, H. Clement11, D. Coderre12, E. Czerwinski13, K. Demmich14, E. Doroshkevich15, R. Engels16, W. Erven17, W. Eyrich18, P. Fedorets19, K. Foehl20, K. Fransson21, F. Goldenbaum22, P. Goslawski23, A. Goswami24, K. Grigoryev25, C. -O. Gullstroem26, F. Hauenstein27, L. Heijkenskjoeld28, V. Hejny29, F. Hinterberger30, M. Hodana31, B. Hoeistad32, A. Jany33, B. R. Jany34, L. Jarczyk35, T. Johansson36, B. Kamys37, G. Kemmerling38, F. A. Khan39, A. Khoukaz40, S. Kistryn41, J. Klaja42, H. Kleines43, B. Klos44, M. Krapp45, W. Krzemien46, P. Kulessa47, A. Kupsc48, K. Lalwani49, D. Lersch50, L. Li51, B. Lorentz52, A. Magiera53, R. Maier54, P. Marciniewski55, B. Marianski56, M. Mikirtychiants57, H. -P. Morsch58, P. Moskal59, B. K. Nandi60, S. Niedzwiecki61, H. Ohm62, I. Ozerianska63, E. Perez del Rio64, P. Plucinski65, P. Podkopal66, D. Prasuhn67, A. Pricking68, D. Pszczel69, K. Pysz70, A. Pyszniak71, C. F. Redmer72, J. Ritman73, A. Roy74, Z. Rudy75, S. Sawant76, S. Schadmand77, A. Schmidt78, T. Sefzick79, V. Serdyuk80, N. Shah81, M. Siemaszko82, R. Siudak83, T. Skorodko84, M. Skurzok85, J. Smyrski86, V. Sopov87, R. Stassen88, J. Stepaniak89, E. Stephan90, G. Sterzenbach91, H. Stockhorst92, H. Stroeher93, A. Szczurek94, T. Tolba95, A. Trzcinski96, R. Varma97, P. Vlasov98, G. J. Wagner99, W. Weglorz100, M. Wolke101, A. Wronska102, P. Wuestner103, P. Wurm104, A. Yamamoto105, X. Yuan106, L. Yurev107, J. Zabierowski108, C. Zheng109, M. J. Zielinski110, W. Zipper111, J. Zlomanczuk112, P. Zupranski113, M. Zurek114
Affiliations: 1WASA-at-COSY collaboration, 2WASA-at-COSY collaboration, 3WASA-at-COSY collaboration, 4WASA-at-COSY collaboration, 5WASA-at-COSY collaboration, 6WASA-at-COSY collaboration, 7WASA-at-COSY collaboration, 8WASA-at-COSY collaboration, 9WASA-at-COSY collaboration, 10WASA-at-COSY collaboration, 11WASA-at-COSY collaboration, 12WASA-at-COSY collaboration, 13WASA-at-COSY collaboration, 14WASA-at-COSY collaboration, 15WASA-at-COSY collaboration, 16WASA-at-COSY collaboration, 17WASA-at-COSY collaboration, 18WASA-at-COSY collaboration, 19WASA-at-COSY collaboration, 20WASA-at-COSY collaboration, 21WASA-at-COSY collaboration, 22WASA-at-COSY collaboration, 23WASA-at-COSY collaboration, 24WASA-at-COSY collaboration, 25WASA-at-COSY collaboration, 26WASA-at-COSY collaboration, 27WASA-at-COSY collaboration, 28WASA-at-COSY collaboration, 29WASA-at-COSY collaboration, 30WASA-at-COSY collaboration, 31WASA-at-COSY collaboration, 32WASA-at-COSY collaboration, 33WASA-at-COSY collaboration, 34WASA-at-COSY collaboration, 35WASA-at-COSY collaboration, 36WASA-at-COSY collaboration, 37WASA-at-COSY collaboration, 38WASA-at-COSY collaboration, 39WASA-at-COSY collaboration, 40WASA-at-COSY collaboration, 41WASA-at-COSY collaboration, 42WASA-at-COSY collaboration, 43WASA-at-COSY collaboration, 44WASA-at-COSY collaboration, 45WASA-at-COSY collaboration, 46WASA-at-COSY collaboration, 47WASA-at-COSY collaboration, 48WASA-at-COSY collaboration, 49WASA-at-COSY collaboration, 50WASA-at-COSY collaboration, 51WASA-at-COSY collaboration, 52WASA-at-COSY collaboration, 53WASA-at-COSY collaboration, 54WASA-at-COSY collaboration, 55WASA-at-COSY collaboration, 56WASA-at-COSY collaboration, 57WASA-at-COSY collaboration, 58WASA-at-COSY collaboration, 59WASA-at-COSY collaboration, 60WASA-at-COSY collaboration, 61WASA-at-COSY collaboration, 62WASA-at-COSY collaboration, 63WASA-at-COSY collaboration, 64WASA-at-COSY collaboration, 65WASA-at-COSY collaboration, 66WASA-at-COSY collaboration, 67WASA-at-COSY collaboration, 68WASA-at-COSY collaboration, 69WASA-at-COSY collaboration, 70WASA-at-COSY collaboration, 71WASA-at-COSY collaboration, 72WASA-at-COSY collaboration, 73WASA-at-COSY collaboration, 74WASA-at-COSY collaboration, 75WASA-at-COSY collaboration, 76WASA-at-COSY collaboration, 77WASA-at-COSY collaboration, 78WASA-at-COSY collaboration, 79WASA-at-COSY collaboration, 80WASA-at-COSY collaboration, 81WASA-at-COSY collaboration, 82WASA-at-COSY collaboration, 83WASA-at-COSY collaboration, 84WASA-at-COSY collaboration, 85WASA-at-COSY collaboration, 86WASA-at-COSY collaboration, 87WASA-at-COSY collaboration, 88WASA-at-COSY collaboration, 89WASA-at-COSY collaboration, 90WASA-at-COSY collaboration, 91WASA-at-COSY collaboration, 92WASA-at-COSY collaboration, 93WASA-at-COSY collaboration, 94WASA-at-COSY collaboration, 95WASA-at-COSY collaboration, 96WASA-at-COSY collaboration, 97WASA-at-COSY collaboration, 98WASA-at-COSY collaboration, 99WASA-at-COSY collaboration, 100WASA-at-COSY collaboration, 101WASA-at-COSY collaboration, 102WASA-at-COSY collaboration, 103WASA-at-COSY collaboration, 104WASA-at-COSY collaboration, 105WASA-at-COSY collaboration, 106WASA-at-COSY collaboration, 107WASA-at-COSY collaboration, 108WASA-at-COSY collaboration, 109WASA-at-COSY collaboration, 110WASA-at-COSY collaboration, 111WASA-at-COSY collaboration, 112WASA-at-COSY collaboration, 113WASA-at-COSY collaboration, 114WASA-at-COSY collaboration

An exclusive measurement of the excitation function for the dd->3Heppi- reaction was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 GeV/c to 2. Read More

2012Dec

Exclusive and kinematically complete high-statistics measurements of the basic double pionic fusion reactions pn -> dpi0pi0, pn -> d pi+pi- and pp -> dpi+pi0 have been carried out simultaneously over the energy region of the ABC effect using the WASA detector setup at COSY. Whereas the isoscalar reaction part given by the dpi0pi0 channel exhibits the ABC effect, i.e. Read More

Here we examine the evolution of irradiated clouds using the Smoothed Particle Hydrodynamics ({\small SPH}) algorithm coupled with a ray-tracing scheme that calculates the position of the ionisation-front at each timestep. We present results from simulations performed for three choices of {\small IR}-flux spanning the range of fluxes emitted by a typical {\small B}-type star to a cluster of {\small OB}-type stars. The extent of photo-ablation, of course, depends on the strength of the incident flux and a strong flux of {\small IR} severely ablates a {\small MC}. Read More

2012Jun

Exclusive and kinematically complete high-statistics measurements of the double pionic fusion reaction $dd \to ^4$He$\pi^0\pi^0$ have been performed in the energy range 0.8 - 1.4 GeV covering thus the region of the ABC effect, which denotes a pronounced low-mass enhancement in the $\pi\pi$-invariant mass spectrum. Read More

We have carried out deep (V$\sim$21 mag) \ubvri photometric study of the star cluster Stock 18. These along with archival Infrared data have been used to derive the basic cluster parameters and also to study the star formation processes in and around the cluster region. The distance to the cluster is derived as 2. Read More

2011Jul
Authors: P. Adlarson, C. Adolph, W. Augustyniak, W. Bardan, M. Bashkanov, T. Bednarski, F. S. Bergmann, M. Berłowski, H. Bhatt, K. -T. Brinkmann, M. Büscher, H. Calén, H. Clement, D. Coderre, E. Czerwiński, E. Doroshkevich, R. Engels, W. Erven, W. Eyrich, P. Fedorets, K. Föhl, K. Fransson, F. Goldenbaum, P. Goslawski, K. Grigoryev, C. -O. Gullström, C. Hanhart, L. Heijkenskjöld, J. Heimlich, V. Hejny, F. Hinterberger, M. Hodana, B. Höistad, M. Jacewicz, A. Jany, B. R. Jany, L. Jarczyk, T. Johansson, B. Kamys, G. Kemmerling, O. Khakimova, A. Khoukaz, S. Kistryn, J. Klaja, H. Kleines, B. Kłos, F. Kren, W. Krzemień, P. Kulessa, A. Kupść, K. Lalwani, S. Leupold, B. Lorentz, A. Magiera, R. Maier, B. Mariański, P. Marciniewski, U. -G. Meißner, M. Mikirtychiants, H. -P. Morsch, P. Moskal, B. K. Nandi, S. Niedźwiecki, H. Ohm, A. Passfeld, C. Pauly, E. Perez del Rio, T. Petri, Y. Petukhov, N. Piskunov, P. Pluciński, P. Podkopał, A. Povtoreyko, D. Prasuhn, A. Pricking, K. Pysz, A. Pyszniak, T. Rausmann, C. F. Redmer, J. Ritman, A. Roy, Z. Rudy, S. Sawant, S. Schadmand, A. Schmidt, T. Sefzick, V. Serdyuk, N. Shah, M. Siemaszko, R. Siudak, T. Skorodko, M. Skurzok, J. Smyrski, V. Sopov, R. Stassen, J. Stepaniak, G. Sterzenbach, H. Stockhorst, F. Stollenwerk, A. Szczurek, A. Täschner, C. Terschlüsen, T. Tolba, A. Trzciński, R. Varma, P. Vlasov, G. J. Wagner, W. Węglorz, A. Winnemöller, A. Wirzba, M. Wolke, A. Wrońska, P. Wüstner, P. Wurm, X. Yuan, L. Yurev, J. Zabierowski, C. Zheng, M. J. Zieliński, W. Zipper, J. Złomańczuk, P. Żuprański

An exclusive measurement of the decay eta --> pi+ pi- gamma has been performed at the WASA facility at COSY. The eta mesons were produced in the fusion reaction pd --> 3He X at a proton beam momentum of 1.7 GeV/c. Read More

2011Jul

The reaction pp->pppi0pi0 has been investigated at a beam energy of 1.4 GeV using the WASA-at-COSY facility. The total cross section is found to be (324 +- 21_systematic +- 58_normalization) mub. Read More

2011Apr
Authors: P. Adlarson, C. Adolph, W. Augustyniak, V. Baru, M. Bashkanov, F. S. Bergmann, M. Berlowski, H. Bhatt, K. -T. Brinkmann, M. Buescher, H. Calen, H. Clement, D. Coderre, E. Czerwinski, E. Doroshkevich, C. Ekstrom, R. Engels, W. Erven, W. Eyrich, P. Fedorets, K. Foehl, K. Fransson, F. Goldenbaum, P. Goslawski, K. Grigoryev, V. Grishina, C. -O. Gullstrom, J. Hampe, C. Hanhart, L. Heijkenskj, V. Hejny, F. Hinterberger, M. Hodana, B. Hoistad, M. Jacewicz, M. Janusz, A. Jany, B. R. Jany, L. Jarczyk, J. Jaus, T. Johansson, B. Kamys, G. Kemmerling, O. Khakimova, A. Khoukaz, S. Kistryn, J. Klaja, H. Kleines, B. Klos, F. Kren, W. Krzemien, P. Kulessa, S. Kullander, A. Kupsc, K. Lalwani, B. Lorentz, A. Magiera, R. Maier, P. Marciniewski, B. Marianski, M. Mikirtychiants, P. Moskal, H. -P. Morsch, B. K. Nandi, H. Ohm, A. Passfeld, C. Pauly, E. Perez del Rio, Y. Petukhov, N. Piskunov, P. Plucinski, P. Podkopal, A. Povtoreyko, D. Prasuhn, A. Pricking, K. Pysz, T. Rausmann, C. F. Redmer, J. Ritman, A. Roy, R. J. M. Y. Ruber, Z. Rudy, S. Schadmand, A. Schmidt, W. Schroeder, T. Sefzick, V. Serdyuk, N. Shah, M. Siemaszko, R. Siudak, T. Skorodko, M. Skurzok, J. Smyrski, V. Sopov, R. Stassen, J. Stepaniak, G. Sterzenbach, H. Stockhorst, H. Stroeher, A. Szczurek, A. Taeschner, T. Tolba, A. Trzcinski, R. Varma, P. Vlasov, G. J. Wagner, W. Weglorz, A. Winnemoeller, A. Wirzba, M. Wolke, A. Wronska, P. Wuestner, P. Wurm, L. Yurev, J. Zabierowski, M. J. Zielinski, W. Zipper, J. Zlomanczuk, P. Zupranski

We report on a high-statistics measurement of the basic double pionic fusion reaction $pn \to d\pi^0\pi^0$ over the energy region of the so-called ABC effect, a pronounced low-mass enhancement in the $\pi\pi$-invariant mass spectrum. The measurements were performed with the WASA detector setup at COSY. The data reveal the ABC effect to be associated with a Lorentzian shaped energy dependence in the integral cross section. Read More

Context. Emission and absorption line profiles which are formed in the interaction of pre-main sequence (PMS) stars and their circumstellar environment are found to be variable at various timescales. Aims. Read More

Aims: We aim to develop a method to determine distances to molecular clouds using JHK near-infrared photometry. Methods: The method is based on a technique that aids spectral classification of stars lying towards the fields containing the clouds into main sequence and giants. In this technique, the observed (J-H) and (H-K_s) colours are dereddened simultaneously using trial values of A V and a normal interstellar extinction law. Read More

Molecular clouds (MCs) are stellar nurseries, however, formation of stars within MCs depends on the ambient physical conditions. MCs, over a free-fall time are exposed to numerous dynamical phenomena, of which, the interaction with a thin, dense shell of gas is but one. Below we present results from self-gravitating, 3-D smoothed particle hydrodynamics ({\small SPH}) simulations of the problem; seven realisations of the problem have been performed by varying the precollision density within the cloud, the nature of the post-collision shock, and the spatial resolution in the computational domain. Read More

We have investigated the young stellar population in and around SFO 38, one of the massive globules located in the northern part of the Galactic HII region IC 1396, using the Spitzer IRAC and MIPS observations (3.6 to 24 micron) and followed up with ground based optical photometric and spectroscopic observations. Based on the IRAC and MIPS colors and H-alpha emission we identify ~45 Young Stellar Objects (Classes 0/I/II) and 13 probable Pre Main Sequence candidates. Read More

We present X-ray emission characteristics of the massive O-type stars DH Cep and HD 97434 using archival XMM-Newton observations. There is no convincing evidence for short term variability in the X-ray intensity during the observations. However, the analysis of their spectra reveals X-ray structure being consistent with two-temperature plasma model. Read More

We present X-ray analysis of two Wolf-Rayet (WR) binaries: V444 Cyg and CD Cru using the data from observations with XMM-Newton. The X-ray light curves show the phase locked variability in both binaries, where the flux increased by a factor of $\sim 2$ in the case of V444 Cyg and $\sim 1.5$ in the case of CD Cru from minimum to maximum. Read More