The XMM Newton and INTEGRAL observations of the supergiant fast X-ray transient IGR J16328-4726

The accretion mechanism producing the short flares observed from the Supergiant Fast X-ray Transients (SFXT) is still highly debated and forms a major part in our attempts to place these X-ray binaries in the wider context of the High Mass X-ray Binaries. We report on a 216 ks INTEGRAL observation of the SFXT IGR J16328-4726 (August 24-27, 2014) simultaneous with two fixed-time observations with XMM Newton (33ks and 20ks) performed around the putative periastron passage, in order to investigate the accretion regime and the wind properties during this orbital phase. During these observations, the source has shown luminosity variations, from 4x10^{34} erg/s to 10^{36} erg/s, linked to spectral properties changes. The soft X-ray continuum is well modeled by a power law with a photon index varying from 1.2 up to 1.7 and with high values of the column density in the range 2-4x10^{23}/cm^2. We report on the presence of iron lines at 6.8-7.1 keV suggesting that the X-ray flux is produced by accretion of matter from the companion wind characterized by density and temperature inhomogeneities

The IBIS soft gamma-ray sky after 1000 INTEGRAL orbits

We report here an all-sky soft gamma-ray source catalog based on IBIS observations performed during the first 1000 orbits of INTEGRAL. The database for the construction of the source list consists of all good quality data available from launch in 2002 up to the end of 2010. This corresponds to $\sim$110 Ms of scientific public observations with a concentrated coverage on the Galactic Plane and extragalactic deep exposures. This new catalog includes 939 sources above a 4.5 sigma significance threshold detected in the 17-100 keV energy band, of which 120 represent previously undiscovered soft gamma-ray emitters. The source positions are determined, mean fluxes are provided in two main energy bands, and are reported together with the overall source exposure. Indicative levels of variability are provided, and outburst times and durations are given for transient sources. Comparison is made with previous IBIS catalogs, and those from other similar missions.Comment: 65 pages, 9 figures, 2 tables, accepted for publication in ApJ Supplement

Additive manufacturing of NiTi architected metamaterials

Additive manufacturing has revolutionized the creation of complex and intrinsic structures, offering tailored designs for enhanced product performance across various applications. Architected cellular or lattice structures exemplify this innovation, customizable for specific mechanical or functional requirements, boasting advantages such as reduced mass, heightened load-bearing capabilities, and superior energy absorption. Nonetheless, their single-use limitation arises from plastic deformation resulting from localized yield damage or plastic buckling. Incorporating NiTi shape memory alloys (SMAs) presents a solution, enabling structures to recover their original shape post-unloading. In this study, an NiTi architected metastructure, featuring auxetic behavior and a negative Poisson's ratio, was designed and fabricated via laser powder bed fusion (LPBF). The samples exhibit promising superelastic performance with recoverable deformation strains at room temperature. Comprehensive characterization processes evaluated the functional performance of the fabricated metastructures. The metastructure geometry promoted microstructure formation primarily along the wall thickness. Cycling compression tests, conducted at three applied force levels, demonstrated stable cyclic behavior with up to 3.8 % reversible deformation strain, devoid of plastic buckling or yielding damage. Furthermore, the NiTi metastructures displayed robust energy absorption capacity and damping behavior, underscoring their potential for reusable energy dissipators in various industries including aerospace, automotive, construction, and etc.</p

Hot isostatic pressing and heat treatments of LPBFed CoCuFeMnNiTi0.13 high-entropy alloy: microstructure and mechanical properties

The present work explores the possibility of processing a CoCuFeMnNiTi0.13 high-entropy alloy by laser powder bed fusion (LPBF). The alloy, produced under optimised processing conditions, presents good densification but also hot cracks, caused by the liquation of an inter-dendritic Cu-rich phase. Microstructure of the as-built alloy is characterised by face centred cubic (FCC) columnar grains, containing Cu-poor dendrites and Cu-rich inter-dendritic areas. The alloy, which was designed to be strengthened by spinodal decomposition and precipitation, was subjected to different thermo-mechanical treatments to try and improve its properties. Direct ageing and solution treatment and ageing produced a strong but brittle material (tensile strength of 683 MPa and elongation to failure of 1.3%), whereas hot isostatic pressing followed by controlled cooling was able to heal pores and cracks while triggering the desired microstructural transformations (spinodal decomposition and precipitation). This resulted into a balanced set of mechanical properties (tensile strength of 473 MPa and elongation to failure of 7.6%). This work shows that proper post-processing can mitigate the issues typically affecting LPBF fabricated HEAs, producing tailored microstructures with satisfactory mechanical performances

Specific immunotherapy for allergic rhinitis in Italy: The patients' points of view

Specific immunotherapy (SIT) is the unique causal treatment for allergy, but its use is quite limited. A perspective, cross-sectional telephone interview survey was carried out in Italy to evaluate the characteristics of 500 patients with allergic rhinitis (250 of whom treated with SIT). Relevant differences were found concerning therapeutic management of allergic rhinitis, mainly regarding the use of drugs and co-morbidities. The allergist is the most important consultant who prescribes SIT. This study therefore provides evidence that the course of allergic rhinitis may depend on the therapy prescribed by and the level of allergy awareness of the physician

Correlated Optical/X-ray Long-term Variability in LMXB 4U1636-536

We have conducted a 3-month program of simultaneous optical, soft and hard X-ray monitoring of the LMXB 4U1636-536/V801 Ara using the SMARTS 1.3m telescope and archival RXTE/ASM and Swift/XRT data. 4U1636-536 has been exhibiting a large amplitude, quasi-periodic variability since 2002 when its X-ray flux dramatically declined by roughly an order of magnitude. We confirmed that the anti-correlation between soft (2-12 keV) and hard (> 20 keV) X-rays, first investigated by Shih et al. (2005), is not an isolated event but a fundamental characteristic of this source's variability properties. However, the variability itself is neither strictly stable nor changing on an even longer characteristic timescale. We also demonstrate that the optical counterpart varies on the same timescale, and is correlated with the soft, and not the hard, X-rays. This clearly shows that X-ray reprocessing in LMXB discs is mainly driven by soft X-rays. The X-ray spectra in different epochs of the variability revealed a change of spectral characteristics which resemble the state change of black hole X-ray binaries. All the evidence suggests that 4U1636-536 is frequently (~monthly) undergoing X-ray state transitions, a characteristic feature of X-ray novae with their wide range of luminosities associated with outburst events. In its current behavioural mode, this makes 4U1636-536 an ideal target for investigating the details of state changes in luminous X-ray binaries.Comment: 7 pages, 6 figures, accepted for publication in MNRA