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The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative new observing capabilities for every area of astrophysics, and to heliophysics and planetary physics as well. LEM's main goal is a comprehensive look at the physics of galaxy formation, including stellar and black-hole feedback and flows of baryonic matter into and out of galaxies. These processes are best studied in X-rays, and emission-line mapping is the pressing need in this area. LEM will use a large microcalorimeter array/IFU, covering a 30x30' field with 10" angular resolution, to map the soft X-ray line emission from objects that constitute galactic ecosystems. These include supernova remnants, star-forming regions, superbubbles, galactic outflows (such as the Fermi/eROSITA bubbles in the Milky Way and their analogs in other galaxies), the Circumgalactic Medium in the Milky Way and other galaxies, and the Intergalactic Medium at the outskirts and beyond the confines of galaxies and clusters. LEM's 1-2 eV spectral resolution in the 0.2-2 keV band will make it possible to disentangle the faintest emission lines in those objects from the bright Milky Way foreground, providing groundbreaking measurements of the physics of these plasmas, from temperatures, densities, chemical composition to gas dynamics. While LEM's main focus is on galaxy formation, it will provide transformative capability for all classes of astrophysical objects, from the Earth's magnetosphere, planets and comets to the interstellar medium and X-ray binaries in nearby galaxies, AGN, and cooling gas in galaxy clusters. In addition to pointed observations, LEM will perform a shallow all-sky survey that will dramatically expand the discovery space., 18 pages. White paper for a mission concept to be submitted for the 2023 NASA Astrophysics Probes opportunity. v2: All-sky survey figure expanded, references fixed. v3: Added energy resolution measurements for prototype detector array. v4: Author list and reference fixes

The LiteBIRD collaboration: et al., arXiv:2111.09140v2, We present a demonstration of the in-flight polarization angle calibration for the JAXA/ISAS second strategic large class mission, LiteBIRD, and estimate its impact on the measurement of the tensor-to-scalar ratio parameter, r, using simulated data. We generate a set of simulated sky maps with CMB and polarized foreground emission, and inject instrumental noise and polarization angle offsets to the 22 (partially overlapping) LiteBIRD frequency channels. Our in-flight angle calibration relies on nulling the EB cross correlation of the polarized signal in each channel. This calibration step has been carried out by two independent groups with a blind analysis, allowing an accuracy of the order of a few arc-minutes to be reached on the estimate of the angle offsets. Both the corrected and uncorrected multi-frequency maps are propagated through the foreground cleaning step, with the goal of computing clean CMB maps. We employ two component separation algorithms, the Bayesian-Separation of Components and Residuals Estimate Tool (B-SeCRET), and the Needlet Internal Linear Combination (NILC). We find that the recovered CMB maps obtained with algorithms that do not make any assumptions about the foreground properties, such as NILC, are only mildly affected by the angle miscalibration. However, polarization angle offsets strongly bias results obtained with the parametric fitting method. Once the miscalibration angles are corrected by EB nulling prior to the component separation, both component separation algorithms result in an unbiased estimation of the r parameter. While this work is motivated by the conceptual design study for LiteBIRD, its framework can be broadly applied to any CMB polarization experiment. In particular, the combination of simulation plus blind analysis provides a robust forecast by taking into account not only detector sensitivity but also systematic effects., This work is supported in Japan by ISAS/JAXA for Pre-Phase A2 studies, by the acceleration program of JAXA research and development directorate, by the World Premier International Research Center Initiative (WPI) of MEXT, by the JSPS Core-to-Core Program of A. Advanced Research Networks, and by JSPS KAKENHI Grant Numbers JP15H05891, JP17H01115, and JP17H01125. The Italian LiteBIRD phase A contribution is supported by the Italian Space Agency (ASI Grants No. 2020-9-HH.0 and 2016-24-H.1-2018), the National Institute for Nuclear Physics (INFN) and the National Institute for Astrophysics (INAF). The French LiteBIRD phase A contribution is supported by the Centre National d’Etudes Spatiale (CNES), by the Centre National de la Recherche Scientifique (CNRS), and by the Commissariat à l’Energie Atomique (CEA). The Canadian contribution is supported by the Canadian Space Agency. The US contribution is supported by NASA grant no. 80NSSC18K0132. Norwegian participation in LiteBIRD is supported by the Research Council of Norway (Grant No. 263011). The Spanish LiteBIRD phase A contribution is supported by the Spanish Agencia Estatal de Investigación (AEI), project refs. PID2019-110610RB-C21 and AYA2017-84185P. Funds that support the Swedish contributions come from the Swedish National Space Agency (SNSA/Rymdstyrelsen) and the Swedish Research Council (Reg. no. 2019-03959). The German participation in LiteBIRD is supported in part by the Excellence Cluster ORIGINS, which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy (Grant No. EXC-2094- 390783311). This research used resources of the Central Computing System owned and operated by the Computing Research Center at KEK, as well as resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy. TM’s work is supported by JSPS KAKENHI Grant Number JP18KK0083. EdlH acknowledges partial financial support from the Concepción Arenal Programme of the Universidad de Cantabria. EdlH, EMG and PV acknowledge the Santander Supercomputación support group at the Universidad de Cantabria, a member of the Spanish Supercomputing Network, who provided access to the Altamira Supercomputer at the Instituto de Física de Cantabria (IFCA-CSIC) for performing simulations and analyses. They also acknowledge funding from Unidad de Excelencia María de Maeztu (MDM-20170765). YM’s work was supported in part by the Japan Society for the Promotion of Science (JSPS) KAKENHI, Grants No. JP20K14497. NK, CB and AG acknowledge financial support from the INFN InDark project and from the COSMOS network (www.cosmosnet.it) through– 22the ASI (Italian Space Agency) Grants 2016-24-H.0 and 2016-24-H.1-2018. EK’s work was supported in part by the JSPS KAKENHI Grant Number JP20H05850 and JP20H05859.

We summarise observations and our current understanding of the interstellar medium (ISM) in galaxies, which mainly consists of three phases: cold atomic or molecular gas and clouds, warm neutral or ionised gas, and hot ionised gas. These three gas phases form thermally stable states, while disturbances are caused by gravitation and stellar feedback in form of photons and shocks in stellar winds and supernovae. Hot plasma is mainly found in stellar bubbles, superbubbles, and Galactic outflows/fountains and is often dynamically unstable and is over-pressurised. In addition, in galactic nuclear regions, accretion onto the supermassive black hole causes enhanced star formation, outflows, additional heating, and acceleration of cosmic rays., Comment: To appear in the Section 'Supernovae, Supernova Remnants, and Diffuse Emission' (Section eds.: Aya Bamba, Keiichi Maeda, Manami Sasaki) in the Handbook of X-ray and Gamma-ray Astrophysics (Eds. Cosimo Bambi, Andrea Santangelo)

Recently, Minkowski Tensors (MT) have gained popularity for morphological analysis tasks. As opposed to the scalar Minkowski functionals (MF; in 2D given by area, perimeter and Euler characteristic), MT can characterize symmetry and orientation of a body. This has been used for a variety of tasks, e.g. to detect interstellar bubbles by tracing back the origins of filaments in HII-regions, or to search for alignment of structures in the CMB. I present a marching-square-based method for calculating MT and MF on the sphere for maps in the Healpix format. MT are calculated for a local neighborhood and can then be summed up/averaged over a larger region, using their additivity property. This provides the possibility of localized analyses looking for CMB anisotropies and non-Gaussianities at varying scales., Comment: Contribution to the 2022 Cosmology session of the 56th Rencontres de Moriond

37th International Cosmic Ray Conference, ICRC 2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 779 (2021). doi:10.22323/1.395.0779, Detecting and studying galactic gamma-ray sources emitting very-high energy photons sheds light on the acceleration and propagation of cosmic rays presumably created in these sources. Currently, there are few sources emitting photons with energies exceeding 100 TeV. In this work we revisit the unidentified source MGRO J1908+06, initially detected by Milagro, using an updated H.E.S.S. dataset and analysis pipeline. The vicinity of the source contains a supernova remnant and pulsars as well as molecular clouds. This makes the identification of the primary source(s) of galactic cosmic rays as well as the nature of the gamma-ray emission challenging, especially in light of the recent HAWC and LHAASO detection of the high energy tail of its spectrum. Exploiting the better angular resolution as compared to particle detectors, we investigate the morphology of the source as well as its spectral properties., Published by SISSA, Trieste

Aims. We present the results of the analysis of five observations of the globular cluster 47 Tucanae (47 Tuc) with eROSITA (extended Roentgen Survey with an Imaging Telescope Array) on board Spektrum-Roentgen-Gamma (Spektr-RG, SRG). The aim of the work is the study of the X-ray population in the field of one of the most massive globular clusters in our Milky Way. We focused on the classification of point-like sources in the field of 47 Tuc. The unresolved dense core of 47 Tuc (1$'$.7 radius) and also the sources, which show extended emission are excluded in this study. Methods. We applied different methods of X-ray spectral and timing analysis together with multi wavelength studies for the classification of the X-rays sources in the field of 47 Tuc. Results. We detected 888 point-like sources in the energy range of 0.2-5.0 keV. We identified 126 background AGNs and 25 foreground stars. One of the foreground stars is classified as a variable M dwarf. We also classified 14 X-ray sources as members of 47 Tuc, including 1 symbiotic stars, 2 quiescent low mass X-ray binaries, and 4 cataclysmic variable. There are also 5 X-ray sources, which can either be a cataclysmic variable or a contact binary, and also 1 X-ray sources which can be an active binary (Type RS CVn). We identified one X-ray binary, which belongs to the Small Magellanic Cloud. Moreover, we calculated the X-ray luminosity function of 47 Tuc. No significant population that seems to belong to the globular cluster has been observed in the energy range of 0.5-2.0 keV using eROSITA observations., Accepted in A&A on 28 Jan 2022, for the Special Issue: The Early Data Release of eROSITA and Mikhail Pavlinsky ART-XC on the SRG Mission. 20 pages, 11 Figures

37th International Cosmic Ray Conference, ICRC2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 777 (2021). doi:10.22323/1.395.0777, Fast radio bursts (FRB) are enigmatic powerful single radio pulses with durations of several milliseconds and high brightness temperatures suggesting coherent emission mechanism. For the time being a number of extragalactic FRBs have been detected in the high-frequency radio band including repeating ones. The most plausible explanation for these phenomena is magnetar hyperflares. The first observational evidence of this scenario was obtained in April 2020 when an FRB was detected from the direction of the Galactic magnetar and soft gamma repeater SGR1935+2154. The FRB was preceded with a number of soft gamma-ray bursts observed by Swift-BAT satellite, which triggered the follow-up program of the H.E.S.S. imaging atmospheric Cherenkov telescopes (IACTs). H.E.S.S. has observed SGR1935+2154 over a 2 hour window few hours prior to the FRB detection by STARE2 and CHIME. The observations overlapped with other X-ray bursts from the magnetar detected by INTEGRAL and Swift-BAT, thus providing first observations of a magnetar in a flaring state in the very-high energy domain. We present the analysis of these observations, discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma repeaters and anomalous X-ray pulsars., Published by SISSA, Trieste

Through a series of simulated observations, we investigate the capability of the instruments aboard the forthcoming THESEUS mission for the detection of a characteristic signal from decaying dark matter (DM) in the keV-MeV energy range. We focus our studies on three well studied Standard Model extensions hosting axion-like particle, dark photon, and sterile neutrino DM candidates. We show that, due to the sensitivity of THESEUS' X and Gamma Imaging Spectrometer (XGIS) instrument, existing constraints on dark matter parameters can be improved by a factor of up to ~300, depending on the considered DM model and assuming a zero level of systematic uncertainty. We also show that even a minimal level of systematic uncertainty of 1% can impair potential constraints by one to two orders of magnitude. We argue that nonetheless, the constraints imposed by THESEUS will be substantially better than existing ones and will well complement the constraints of upcoming missions such as eXTP and Athena. Ultimately, the limits imposed by THESEUS and future missions will ensure a robust and thorough coverage of the parameter space for decaying DM models, enabling either a detection of dark matter or a significant improvement of relevant limits., to match accepted for publication in Phys. Rev. D. version

Supernova remnants serve as nearby laboratories relevant to many areas in Astrophysics, from stellar and galaxy evolution to extreme astrophysics and the formation of the heavy elements in the Universe. The Chandra X-ray mission has enabled a giant leap forward in studying both SNRs and their compact stellar remnants on sub-arcsecond scale. However, such high-resolution imaging studies have been mostly limited to the nearby and/or relatively bright objects. There is no question that we are missing a large population, especially in external galaxies. Within our own Galaxy, we are presented with new fundamental questions related to neutron stars' diversity, kicks, relativistic winds and the way these objects interact with, and impact, their host environments. In this white paper, we highlight some of the breakthroughs to be achieved with future X-ray missions (such as the proposed AXIS probe) equipped with sub-arcsecond imaging resolution and an order of magnitude improvement in sensitivity., Astro2020 Science White Paper. 9 pages, 2 figures

大気球シンポジウム 平成22年度(2010年9月1日-10月1日. 宇宙航空研究開発機構宇宙科学研究所), 相模原市, 神奈川県, Balloon Symposium 2010 (September 30-October 1, 2010. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)), Sagamihara, Kanagawa Japan, 資料番号: AA0065074020

This paper reports an application of the 0-1 programming model to the regression testing plan for an industrial software. The key idea is to formulate a testing plan as a 0-1 programming problem (Knapsack problem). The empirical study shows that the 0-1 programming method can produce a cost-effective testing plan in which all potential regressions are found at only 22% of the cost of running all test cases.

We report the detection of molecular clouds around the X-ray bright interior feature in the Galactic supernova remnant (SNR) CTB 109 (G109.1-1.0). This feature, called the Lobe, has been previously suggested to be the result of an interaction of the SNR shock wave with a molecular cloud complex. We present new high resolution X-ray data from the Chandra X-ray Observatory and new high resolution CO data from the Five College Radio Observatory which show the interaction region with the cloud complex in greater detail. The CO data reveal three clouds around the Lobe in the velocity interval -57 < v < -52 km s^-1. The velocity profiles of 12CO at various parts of the east cloud are well fit with a Gaussian; however, at the position where the CO cloud and the Lobe overlap, the velocity profile has an additional component towards higher negative velocities. The molecular hydrogen density in this part of the cloud is relatively high (N_H2 = 1.9 x 10^20 cm^-2), whereas the foreground absorption in X-rays (N_H = 4.5 x 10^21 cm^-2), obtained from Chandra data, is lower than in other parts of the cloud and in the north and south cloud. These results indicate that this cloud has been hit by the SNR blast wave on the western side, forming the bright X-ray Lobe., Accepted for publication in ApJL. 3 figures

We present FUSE and XMM-Newton data for the reverse shock of the O-rich SNR 1E0102.2-7219 in the SMC. The FUSE observations cover three regions with significantly different optical [O III] intensities, all associated with the relatively bright part of the X-ray ring. Emission lines of O VI 1032, 1038 are clearly detected in the FUSE spectra. By combining this O VI doublet emission with the O VII triplet and O VIII Lyalpha fluxes from the XMM-Newton spectra and assuming a non-equilibrium ionization model with a single ionization timescale for the spectra, we are able to find a narrow range of temperatures and ionization timescales that are consistent with the respective line ratios. However, if we assume a plane-parallel shock model with a distribution of ionization timescales, the O VI emission appears to be inconsistent with O VII and O VIII in X-rays. We also analyze the total XMM-Newton EPIC-MOS 1/2 spectra for the three regions. The X-ray spectra are dominated by strong emission lines of O, Ne, and Mg, however, we detect an emission component that accounts for 14 - 25% of the flux and can be attributed to shocked ISM. We find that there is no consistent set of values for the temperature and ionization timescale which can explain the observed line ratios for O, Ne, and Mg. This would be consistent with a structured distribution of the ejecta as the O, Ne, Mg would have interacted with the reverse shock at different times., Comment: 28 pages, 5 figues, Fig. 1 as JPEG. To be published in ApJ (01 May 2006, v. 642, 1 issue)

This thesis presents the analysis of five XMM-Newton observations of the Draco dwarf spheroidal galaxy (dSph) in X-rays. We performed source detection sepa- rately for each image in each observation and for the total band mosaic image and produced a catalogue of 70 X-ray sources. The sources were classified through cross-correlation with catalogues of other wavelengths, spectral analysis, hardness ratio diagrams, and variability studies. We classified 18 sources as active galac- tic nuclei (AGNs) and 9 sources as galaxies and galaxy candidates. Six sources were classified as foreground stars and one source as a foreground contact binary system in the Milky Way. Four sources were classified as Low-mass X-ray bi- nary (LMXB) candidates. One of them shows a significant pulsation, while the others were classified based on the X-ray-to-optical flux ratio and their positionthe colour-magnitude diagram. We also found a symbiotic star, a candidate forcataclysmic variable, and a binary system in the Draco dSph. Based on hardness ratios we classified 9 hard sources, which can be AGNs or LMXBs, in the fieldthe Draco dSph. In the next step, the X-ray luminosity functions (XLFs) of the X-ray sourcesthe energy ranges of 2.0 − 10 keV and 0.5 − 2 keV were derived. The XLFs indicate that X-ray sources in the field of the Draco dSph are strongly contaminated by AGNs. The 0.2−5 keV XLF shows an excess of about ten sources, which are most likely objects in Draco dSph. The studies of XLFs were continued by deriving the XLFs of five other dwarf galaxies, Phoenix, Fornax, Leo I, UMi, and UMa II, based on the observations of XMM-Newton in the energy range of 0.5 − 2 keV. We studied the star forma- tion history of each galaxy using literature, and showed that there is a correlation between the population of X-ray binaries and the recent star formation history of dwarf galaxies. The normalised XLF of Phoenix and Leo I dSphs represent the XLF of dwarf galaxies before completely leaving the star forming ages. The XLF shows that dwarf galaxies in this stage contain a population of LMXBs with luminosities of log~ 34 − 35 erg/s. The XLFs of old dSph (Draco, UMi, and UMa II) show that their X-ray sources have very low luminosity ranges log ~ 32 − 1034 erg /s . Therefore, it seems that they are dominated by white-dwarf binaries and/or faint transient LMXBs. In the case of the Fornax dSph, we found an unexpected luminosity range for its X-ray sources, inconsistent with the recent star formation history of the galaxy. We suggested a possible correlation between the nature of the X-ray sources of Fornax and the structure of the galaxy (its dark matter halo). However, more studies of the nature of X-ray sources in this galaxy are necessary. In the last part of the studies, we estimated dark matter halo mass that is required to keep the LMXBs of the Draco dSph, on the basis of the escape velocity of the LMXBs. We considered dark matter halo masses, suggested by different models, and showed that this galaxy could retain its LMXBs with speeds of 70 km/s assuming a dark halo mass of 10^9 solar masses.

The hot interstellar medium (ISM) is defined as the plasma which can be found between the stars of a galaxy and has a temperature of 10^6 – 10^7 K. Within the scope of this thesis, the hot ISM of the supergiant shell LMC-SGS 2 and the HII region DEM L299 in the Large Magellanic Cloud have been studied. It was shown that DEM L299 harbors not only the supernova remnant SNR B0543-68.9 in projection, as believed up to now, but also a superbubble. A multi-frequency morphological study was performed in X-ray, optical, and radio wavelengths in order to study the distribution of the hot, the warm, and the cold ISM of this region. In addition, an X-ray spectral analysis has been performed for LMC-SGS 2, SNR B0543-68.9, the DEM L299 superbubble, and the superbubble blowout.