(C7H11N2)2MBr4 (M = Cu, Zn): X‐Ray Sensitive 0D Hybrid Metal Halides with Tunable Broadband Emission

Aims. The nearby TeV blazar 1ES 1959+650 (z = 0.047) was reported to be in flaring state during June–July 2016 by Fermi-LAT, FACT, MAGIC and VERITAS collaborations. We studied the spectral energy distributions (SEDs) in different states of the flare during MJD 57530–57589 using simultaneous multiwaveband data with the aim of understanding the possible broadband emission scenario during the flare. Methods. The UV-optical and X-ray data from UVOT and XRT respectively on board Swift and high energy γ-ray data from Fermi-LAT were used to generate multiwaveband lightcurves as well as to obtain high flux states and quiescent state SEDs. The correlation and lag between different energy bands was quantified using discrete correlation function. The synchrotron self-Compton (SSC) model was used to reproduce the observed SEDs during flaring and quiescent states of the source. Results. A good correlation is seen between X-ray and high energy γ-ray fluxes. The spectral hardening with increase in the flux is seen in X-ray band. The power law index vs. flux plot in γ-ray band indicates the different emission regions for 0.1–3 GeV and 3–300 GeV energy photons. Two zone SSC model satisfactorily fits the observed broadband SEDs. The inner zone is mainly responsible for producing synchrotron peak and high energy γ-ray part of the SED in all states. The second zone is mainly required to produce less variable optical-UV and low energy γ-ray emission. Conclusions. Conventional single zone SSC model does not satisfactorily explain broadband emission during observation period considered. There is an indication of two emission zones in the jet which are responsible for producing broadband emission from optical to high energy γ-rays.

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Multiwavelength Milky Way: An Educational Poster

Symposium - International Astronomical Union ◽

10.1017/s0074180900128682 ◽

1998 ◽

Vol 179 ◽

pp. 237-237 ◽

Cited By ~ 1

Author(s):

D. Leisawitz ◽

S.W. Digel ◽

S. Geitz

Keyword(s):

Milky Way ◽

Gamma Ray ◽

Line Emission ◽

Electromagnetic Spectrum ◽

Data Sets ◽

X Ray ◽

Nasa Goddard Space ◽

Broadband Emission ◽

The Galaxy ◽

Effective Use

The Astrophysics Data Facility at NASA Goddard Space Flight Center supports the processing, management, and dissemination of data obtained by past, current, and future NASA and international astrophysics missions, and promotes the effective use of those data by the astrophysics community, educators, and the public. Our Multiwavelength Milky Way poster was printed for broad distribution. It depicts the Galaxy at radio, infrared, optical, X-ray, and gamma-ray wavelengths. In particular, the poster contains images of the Galactic 21-cm and CO (J = 1 → 0) line emission, and IRAS 12, 60, and 100 μm, COBE/DIRBE 1.25, 2.2, and 3.5 μm, Digitized Sky Survey optical wavelength, ROSAT/PSPC 0.25, 0.75, and 1.5 keV X-ray, and CGRO/EGRET E > 100 MeV gamma ray broadband emission. All of the data sets are publicly available. Captions describe the Milky Way and what can be learned about the Galaxy from measurements made in each segment of the electromagnetic spectrum. The poster is intended to be an educational tool, one that will stimulate heightened awareness by laypersons of NASA's contribution to modern astronomy.Through an interface available on the World Wide Web at http://adf.gsfc.nasa.gov/adf/adf.html one may view the images that appear on the poster, read the poster captions, and locate the archived data and references.

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Investigation of mesitylene-solvated group 13 mixed-metal halides: syntheses and crystal structures of bis(1,3,5-trimethylbenzene)gallium(I) tetrachlorido- and tetrabromidoaluminate(III) and (1,3,5-trimethylbenzene)gallium(I) tetraiodidoaluminate(III). Variation of the gallium-π-arene bond strength

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0139 ◽

2019 ◽

Vol 74 (10) ◽

pp. 773-782

Author(s):

Luca Küppers ◽

Walter Frank

Keyword(s):

Structure Type ◽

Monoclinic Space Group ◽

Metal Halides ◽

Group 13 ◽

Space Group ◽

X Ray ◽

Mixed Metal ◽

Main Group Metal ◽

Arene Complex ◽

Polymeric Chains

AbstractBis(1,3,5-trimethylbenzene)gallium(I) tetrachloridoaluminate(III), [(1,3,5-(CH3)3C6H3)2Ga][AlCl4] (1), bis(1,3,5-trimethylbenzene)gallium(I) tetrabromidoaluminate(III), [(1,3,5-(CH3)3C6H3)2Ga][AlBr4] (2) and (1,3,5-trimethylbenzene)gallium(I) tetraiodidoaluminate(III), [1,3,5-(CH3)3C6H3Ga][AlI4] (3) were synthesized from the corresponding subvalent GaI/AlIII mixed metal halides and characterized via C,H analysis, Raman spectroscopy, X-ray powder diffraction and X-ray single crystal diffraction. Compound 1 crystallizes in the noncentrosymmetric monoclinic space group Cc isotypic to [(1,3,5-(CH3)3C6H3)2Ga][GaCl4]. For 2 and 3 the monoclinic space group P21/n is found, however, they are neither isotypic nor homotypic. While 2 is isotypic to [(1,3,5-(CH3)3C6H3)2In][InBr4], 3 establishes a new structure type. In the solids of all three title compounds coordination polymeric chains are found, in 1 and 2 built up from bis(arene)-coordinated, in 3 from mono(arene)-coordinated Ga+ ions and the corresponding AlX4− anions in a 1κCl:2κCl′ (1), 1κCl,Cl′:2κCl″ (2) or 1κCl,Cl′:2κCl″:3κCl‴ (3) bridging mode. Taking into account the weaker coordinating character of the AlCl4− as compared to the AlBr4− anion, in line with expectations the number of gallium halogen contacts is increased and the strength of the π-arene bonding is reduced in the bromide 2 as compared to the chloride 1. Finally, with the even more strongly coordinating AlI4− anion the arene coordination is limited to one molecule. Considering mesitylene complexes of gallium, the formation of a mono(arene) complex is unprecedented and even considering group 13 elements in general, the formation of a mono(mesitylene) complex like 3 is unusual. Furthermore, compound 3 is the first structurally characterized arene solvate of a main group metal tetraiodidometallate.

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A year in the life of GW170817: the rise and fall of a structured jet from a binary neutron star merger

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2248 ◽

2019 ◽

Cited By ~ 28

Author(s):

E Troja ◽

H van Eerten ◽

G Ryan ◽

R Ricci ◽

J M Burgess ◽

...

Keyword(s):

Neutron Star ◽

Rapid Decline ◽

Late Time ◽

Time Behavior ◽

X Rays ◽

X Ray ◽

Binary Neutron Star ◽

Long Afterglow ◽

Broadband Emission ◽

Turn Over

Abstract We present the results of our year-long afterglow monitoring of GW170817, the first binary neutron star (NS) merger detected by advanced LIGO and advanced Virgo. New observations with the Australian Telescope Compact Array (ATCA) and the Chandra X-ray Telescope were used to constrain its late-time behavior. The broadband emission, from radio to X-rays, is well-described by a simple power-law spectrum with index β ∼0.585 at all epochs. After an initial shallow rise ∝ t0.9, the afterglow displayed a smooth turn-over, reaching a peak X-ray luminosity of LX≈5 ×1039 erg s−1 at 160 d, and has now entered a phase of rapid decline, approximately ∝ t−2. The latest temporal trend challenges most models of choked jet/cocoon systems, and is instead consistent with the emergence of a relativistic structured jet seen at an angle of ≈22○ from its axis. Within such model, the properties of the explosion (such as its blastwave energy EK ≈ 2 × 1050 erg, jet width θc ≈4○, and ambient density n ≈3 × 10−3 cm−3) fit well within the range of properties of cosmological short GRBs.

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Transition Metal Pnictide Synthesis: Self Propagating Reactions Involving Sodium Arsenide, Antimonide and Bismuthide

Zeitschrift für Naturforschung B ◽

10.1515/znb-1994-0408 ◽

1994 ◽

Vol 49 (4) ◽

pp. 477-482 ◽

Cited By ~ 12

Author(s):

Andrew L. Hector ◽

Ivan P. Parkin

Keyword(s):

Transition Metal ◽

Powder Diffraction ◽

Metal Halides ◽

X Ray ◽

Ft Ir ◽

Cu And Zn

Initiation of the reaction between Na 3E (E = As, Sb, Bi) and anhydrous metal halides at 25 to 550 °C produces metal arsenides MxAsy (M=Y,La, Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Pt ,Cu and Zn) and antimonides MxSby (M=Ti, V, Nb, Ta, Cr, Fe, Co, Ni, Pt, Cu and Zn) via an exothermic selfpropagating reaction. The metal arsenides were characterized by X-ray powder diffraction, SEM/EDAX , microanalysis and FT-IR.

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