Detailed Physical Modeling Reveals the Magnetar Nature of a Transient Anomalous X-ray Pulsar

Anomalous X-ray Pulsars (AXPs) belong to a class of neutron stars believed to harbor the strongest magnetic fields in the universe, as indicated by their energetic bursts and their rapid spindowns. However, a direct measurement of their surface field strengths has not been made to date. It is also not known whether AXP outbursts result from changes in the neutron star magnetic field or crust properties. Here we report the first, spectroscopic measurement of the surface magnetic field strength of an AXP, XTE J1810-197, and solidify its magnetar nature. The field strength obtained from detailed spectral analysis and modeling is remarkably close to the value inferred from the rate of spindown of this source and remains nearly constant during numerous observations spanning over two orders of magnitude in source flux. The surface temperature, on the other hand, declines steadily and dramatically following the 2003 outburst of this source. Our findings demonstrate that heating occurs in the upper neutron star crust during an outburst and sheds light on the transient behaviour of AXPs

SAS-2 observations of the diffuse gamma radiation in the galactic latitude interval 10 deg absolute b or equal to 90 deg

An analysis of all of the second small astronomy satellite gamma-ray data for galactic latitudes with the absolute value of b 10 deg has shown that the intensity varies with galactic latitude, being larger near 10 deg than 90 deg. For energies above 100 MeV the gamma-ray data are consistent with a latitude distribution of the form I(b) = C sub 1 + C sub 2/sin b, with the second term being dominant. This result suggests that the radiation above 100 MeV is coming largely from local regions of the galactic disk. Between 35 and 100 MeV, a similar equation is also a good representation of the data, but here the two terms are comparable. These results indicate that the diffuse radiation above 35 MeV consists of two parts, one with a relatively hard galactic component and the other an isotropic, steep spectral component which extrapolates back well to the low energy diffuse radiation. The steepness of the diffuse isotropic component places significant constraints on possible theoretical models of this radiation

High energy gamma ray results from the second small astronomy satellite

A high energy (35 MeV) gamma ray telescope employing a thirty-two level magnetic core spark chamber system was flown on SAS 2. The high energy galactic gamma radiation is observed to dominate over the general diffuse radiation along the entire galactic plane, and when examined in detail, the longitudinal and latitudinal distribution seem generally correlated with galactic structural features, particularly with arm segments. The general high energy gamma radiation from the galactic plane, explained on the basis of its angular distribution and magnitude, probably results primarily from cosmic ray interactions with interstellar matter

Cyg X-3: Not seen in high-energy gamma rays by COS-B

COS-B had Cyg X-3 within its field of view during 7 observation periods between 1975 and 1982 for in total approximately 300 days. In the skymaps (70 meV E 5000 meV) of the Cyg-X region produced for each of these observations and in the summed map, a broad complex structure is visible in the region 72 deg approximately less than 1 approximately less than 85 deg, approximately less than 5 deg. No resolved source structure is visible at the position of Cyg X-3, but a weak signal from Cyg X-3 could be hidden in the structured gamma-ray background. Therefore, the data has been searched for a 4.8 h timing signature, as well as for a source signal in the sky map in addition to the diffuse background structure as estimated from tracers of atomic and molecular gas

Lynx Mission Concept Status

Lynx is a concept under study for prioritization in the 2020 Astrophysics Decadal Survey. Providing orders of magnitude increase in sensitivity over Chandra, Lynx will examine the first black holes and their galaxies, map the large-scale structure and galactic halos, and shed new light on the environments of young stars and their planetary systems. In order to meet the Lynx science goals, the telescope consists of a high-angular resolution optical assembly complemented by an instrument suite that may include a High Definition X-ray Imager, X-ray Microcalorimeter and an X-ray Grating Spectrometer. The telescope is integrated onto the spacecraft to form a comprehensive observatory concept. Progress on the formulation of the Lynx telescope and observatory configuration is reported in this paper

Hamster polyomavirus-derived virus-like particles are able to transfer in vitro encapsidated plasmid DNA to mammalian cells

The authentic major capsid protein 1 (VP1) of hamster polyomavirus (HaPyV) consists of 384 amino acid (aa) residues (42 kDa). Expression from an additional in-frame initiation codon located upstream from the authentic VP1 open reading frame (at position -4) might result in the synthesis of a 388 aa-long, amino-terminally extended VP1 (aa -4 to aa 384; VP1(ext)). In a plasmid-mediated Drosophila Schneider (S2) cell expression system, both VP1 derivatives as well as a VP1(ext) variant with an amino acid exchange of the authentic Met1Gly (VP1(ext-M1)) were expressed to a similar high level. Although all three proteins were detected in nuclear as well as cytoplasmic fractions, formation of virus-like particles (VLPs) was observed exclusively in the nucleus as confirmed by negative staining electron microscopy. The use of a tryptophan promoter-driven Escherichia coli expression system resulted in the efficient synthesis of VP1 and VP1(ext) and formation of VLPs. In addition, establishment of an in vitro disassembly/reassembly system allowed the encapsidation of plasmid DNA into VLPs. Encapsidated DNA was found to be protected against the action of DNase I. Mammalian COS-7 and CHO cells were transfected with HaPyV-VP1-VLPs carrying a plasmid encoding enhanced green fluorescent protein (eGFP). In both cell lines eGFP expression was detected indicating successful transfer of the plasmid into the cells, though at a still low level. Cesium chloride gradient centrifugation allowed the separation of VLPs with encapsidated DNA from 'empty' VLPs, which might be useful for further optimization of transfection. Therefore, heterologously expressed HaPyV-VP1 may represent a promising alternative carrier for foreign DNA in gene transfer applications

Scintillating fiber detectors for the HypHI project at GSI

WOS: 000270326800009The construction and properties of three sets of two-dimensional scintillating fiber detector arrays for tracking of charged particles used in the HypHI Phase 0 experiment at GSI will be reported in this paper. The position resolutions and the detection efficiency of detectors have been obtained for each layer of detectors by using Li-6 primary beams and particles with Z = 1 produced by fragment reactions of Xe-136 projectiles on the hydrogen target. Besides, the response of energy deposition of charged particles in the first detector set placed right behind the target has been studied by using light projectile fragments with Z = 1, 2 and 3 produced by Ni-58 and C-12 beams. Extracted resolutions for energy deposition and position as well as the detection efficiency fulfill the requirements of the HypHl Phase 0 experiment. (C) 2009 Elsevier B.V. All rights reserved.Helmholtz association as Helmholtz-University Young Investigators Group [VH-NG-239]; German Research Foundation (DFG) [SA 1696/1-1]; Ministry of Education, Science and Culture of Japan [18042008]; EU FP7 HadronPhysic2 SPHEREWe would like to thank the accelerator department at GSI for providing us beams with excellent conditions. We would also thank H. lwase, R. Pleskac and D. Schardt to help us during the experiment in cave A at GSI. We would like to show our appreciation to the FOPI and SPALADIN collaboration to provide us beams behind their experimental setups. We would also like to show our gratitude to the Detector Laboratory at GSI, Electronics Department of the Institute for Nuclear Physics of Mainz University, the Experimental Electronics Department at GSI and the Target Laboratory at GSI for their supports for the development. The HypHI project is funded by the Helmholtz association as Helmholtz-University Young Investigators Group VH-NG-239 at GSI, and German Research Foundation (DFG) with a contract number SA 1696/1-1. The authors acknowledge financial support by the Ministry of Education, Science and Culture of Japan, Grantin-Aid for Scientific Research on Priority Areas 449. This work is also supported by the Ministry of Education, Science and Culture of Japan, Grant-in-Aids for Scientific Research 18042008 and EU FP7 HadronPhysic2 SPHERE

Summary of the HypHI Phase 0 experiment and future plans with FRS at GSI (FAIR Phase 0)

WOS: 000381331200014Results of the HypHI Phase 0 experiment with the reaction of Li-6+C-12 at 2 A GeV are summarised. Invariant mass distributions as well as,the lifetime measurements for H-3(Lambda) and H-4(Lambda) are discussed. The lifetime values for both the hypernuclei are respectively observed to be 18(-32)(+42) ps and 140(-33)(+48) ps, being significantly shorter than those of the Lambda-hyperon. Statistical analyses of existing lifetime data for H-3(Lambda) up to 2014 confirm a significantly short lifetime of H-3(Lambda), which is not explained by present models. Observed hypernuclear production cross section values for H-3(Lambda) and H-4(Lambda) are also summarised. In addition, observed signals for the final states of d + pi(-) and t + pi(-) are discussed. All the discussions on the results of the HypHI Phase 0 experiment in this article are based on [1-4]. We also present a new proposed experiment with the FRS (FRagment Separator) at GSI (FAIR Phase 0) to improve the precision of the hypernuclear spectroscopy with peripheral heavy ion induced reactions. (C) 2016 Elsevier B.V. All rights reserved.GSI Department of Accelerator; GSI Department of Experimental Electronics; GSI Department of the Detector Laboratory; GSI Department of the Target Laboratory; Electronics Department of the Institute for Nuclear Physics of Mainz University; Helmholtz association as Helmholtz-University Young Investigators Group [VH-NG-239]; German Research Foundation (DFG) [SA 1696/1-1]; Ministry of Education, Culture, Sports, Science, and Technology [449, 18042008]; EU FP7 Hadron-Physics-2 SPHEREThe authors would like to thank the GSI Departments of Accelerator, of Experimental Electronics, of the Detector Laboratory and of the Target Laboratory and the Electronics Department of the Institute for Nuclear Physics of Mainz University for supporting the project. The HypHI project is funded by the Helmholtz association as Helmholtz-University Young Investigators Group VH-NG-239 at GSI, and the German Research Foundation (DFG) under contract number SA 1696/1-1. The authors acknowledge the financial support provided by the Ministry of Education, Culture, Sports, Science, and Technology, Grant-in-Aid for Scientific Research on Priority Areas 449, and Grant-in-Aid for promotion of Cooperative Research in Osaka Electro-Communication University (2004-2006). This work is also supported by the Ministry of Education, Culture, Sports, Science, and Technology, Grants-in-Aid for Scientific Research 18042008 and EU FP7 Hadron-Physics-2 SPHERE. A part of this work was carried out on the HIMSTER high performance computing infrastructure provided by the Helmholtz-Institute Mainz