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Está depositada la versión preprint del artículo, We report a detailed study of an unidentified gamma-ray source located in the region of the compact stellar cluster NGC 3603. This is a star-forming region (SFR) powered by a massive cluster of OB stars. A dedicated analysis of about 10 yr of data from 10 GeV to 1 TeV, provided by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope, yields the detection of a pointlike source at a significance of 9 sigma. The source photon spectrum can be described by a power-law model with a best-fit spectral index of 2.35 0.03. In addition, the analysis of a deep Chandra image in the 0.5-7 keV band reliably rules out an extragalactic origin for the gamma-rays. We also conclude that the broadband spectral energy distribution of the point source can be explained well with both leptonic and hadronic models. No firm evidence of association with any other classes of known gamma-ray emitters is found; therefore, we speculate that 4FGL J1115.1-6118 is a gamma-ray-emitting SFR., Ministerio de Economía y Competitividad (España), ERDF under the Spanish MINECO, Ramon and Cajal program, Istituto Nazionale Astrofisica (INAF), Agenzia Spaziale Italiana (ASI), United States Department of Energy (DOE), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2023 The Authors. We are grateful to the referee for a very thorough report that helped us improve the quality of the paper. DFA work is funded by a Consejo Nacional de Ciencia y Tecnología (CONACyT, México) grant through project A1-S22784. This publication is based on data obtained with the MEGARA instrument at the GTC, installed in the Spanish Observatorio del Roque de los Muchachos, in the island of La Palma. MEGARA has been built by a Consortium led by the Universidad Complutense de Madrid (Spain) and that also includes the Instituto de Astrofísica, Óptica y Electrónica (INAOE, México), Instituto de Astrofísica de Andalucía (CSIC, Spain), and the Universidad Politécnica de Madrid (Spain). MEGARA is funded by the Consortium institutions, GRANTECAN S.A. and European Regional Development Funds (ERDF), through Programa Operativo Canarias FEDER 2014-2020. YDM thanks CONACYT for the research grant CB-A1-S-25070 and DRG for the research grant CB-A1-S-22784 from which the postdoctoral grant that supported DFA was obtained. RC also thanks CONACyT for the research grant CF-320152. RA acknowledges support from ANID Fondecyt Regular 1202007. ALGM acknowledges support from the Spanish Ministry of Science and Innovation, project PID2019-107408GB-C43 (ESTALLIDOS), and from Gobierno de Canarias through EU FEDER funding, project PID2020010050. JMA acknowledges the support of the Viera y Clavijo Senior program funded by ACIISI and ULL. JIP acknowledges finantial support from projects Estallidos6 AYA2016-79724-C4 (Spanish Ministerio de Economía y Competitividad), Estallidos7 PID2019-107408GB-C44 (Spanish Ministerio de Ciencia e Innovación), grant P18-FR-2664 (Junta de Andalucía), and grant SEV-2017-0709 “Center of Excellence Severo Ochoa Program” (State Agency for Research of the Spanish MCIU)., We present a spatially resolved spectroscopic study for the metal poor H_(II) galaxy J084220+115000 using MEGARA Integral Field Unit observations at the Gran Telescopio Canarias. We estimated the gas metallicity using the direct method for oxygen, nitrogen and helium and found a mean value of 12+log(O/H)=8.03±0.06, and integrated electron density and temperature of ∼ 161 cm^(−3) and ∼ 15400 K, respectively. The metallicity distribution shows a large range of ∆(O/H) = 0.72 dex between the minimum and maximum (7.69±0.06 and 8.42±0.05) values, unusual in a dwarf starforming galaxy. We derived an integrated log(N/O) ratio of −1.51 ± 0.05 and found that both N/O and O/H correspond to a primary production of metals. Spatially resolved maps indicate that the gas appears to be photoionized by massive stars according to the diagnostic line ratios. Between the possible mechanisms to explain the starburst activity and the large variation of oxygen abundance in this galaxy, our data support a possible scenario where we are witnessing an ongoing interaction triggering multiple star-forming regions localized in two dominant clumps., Consejo Nacional de Ciencia y Tecnología (CONACyT, México), Universidad Complutense de Madrid, Instituto de Astrofísica, Óptica y Electrónica (INAOE, México), Instituto de Astrofísica de Andalucía, Universidad Politécnica de Madrid, GRANTECAN S.A, European Regional Development Funds (ERDF), through Programa Operativo Canarias FEDER 2014-2020, ANID Fondecyt Regular, Ministerio de Ciencia e Innovación, Gobierno de Canarias through EU FEDER funding, Viera y Clavijo Senior program funded by ACIISI and ULL, Ministerio de Economía y Competitividad Project Estallidos6, Ministerio de Economía y Competitividad Project Estallidos7, Junta de Andalucía, “Center of Excellence Severo Ochoa Program”, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2014. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The support of the German BMBF and MPG, the Italian INFN, the Swiss National Fund SNF, and the Spanish MICINN is gratefully acknowledged. This work was also supported by the CPAN CSD2007-00042 and MultiDark CSD2009-00064 projects of the Spanish Consolider-Ingenio 2010 programme, by grant 127740 of the Academy of Finland, by the DFG Cluster of Excellence “Origin and Structure of the Universe”, by the Croatian Science Foundation Project 09/176, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, and by the Polish MNiSzW grant 745/N-HESSMAGIC/2010/0., Aims. HESS J1857+026 is an extended TeV gamma-ray source that was discovered by H. E. S. S. as part of its Galactic plane survey. Given its broadband spectral energy distribution and its spatial coincidence with the young energetic pulsar PSR J1856+0245, the source has been put forward as a pulsar wind nebula (PWN) candidate. MAGIC has performed follow-up observations aimed at mapping the source down to energies approaching 100 GeV in order to better understand its complex morphology. Methods. HESS J1857+026 was observed by MAGIC in 2010, yielding 29 h of good quality stereoscopic data that allowed us to map the source region in two separate ranges of energy. Results. We detected very-high-energy gamma-ray emission from HESS J1857+026 with a significance of 12 sigma above 150 GeV. The differential energy spectrum between 100 GeV and 13 TeV is described well by a power law function dN/dE = N-0(E/1TeV)(-Gamma) with N-0 = (5.37 +/- 0.44(stat) +/- 1.5(sys)) X 10(-12) (TeV-1 cm(-2) s(-1)) and Gamma = 2.16 +/- 0.07(stat) +/- 0.15(sys), which bridges the gap between the GeV emission measured by Fermi-LAT and the multi-TeV emission measured by H.E.S.S.. In addition, we present a detailed analysis of the energy-dependent morphology of this region. We couple these results with archival multiwavelength data and outline evidence in favor of a two-source scenario, whereby one source is associated with a PWN, while the other could be linked with a molecular cloud complex containing an HII region and a possible gas cavity., German BMBF, German MPG, Italian INFN, Swiss National Fund SNF, Spanish MICINN, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

We present a python software repository implementing the PyGMMis (Melchior & Goudling 2018) method to astronomical data cubes of velocity resolved line observations. This implementation is described extensively in Tiwari et al. 2023, ApJ. An example is included in /example/ containing the SOFIA data of RCW120 used in Tiwari et al. 2023, ApJ, along with example scripts describing the full implementation of our code. The majority of parameter tweaking can be performed within 'rcw120-params.txt' which is continuously called during the procedure. A full description of the code and how to use it is in README.md (markdown file).

We report the first detection of deuterated water (HDO) toward an extragalactic hot core. The HDO 2(11)-2(12) line has been detected toward hot cores N 105-2 A and 2 B in the N 105 star-forming region in the low-metallicity Large Magellanic Cloud (LMC) dwarf galaxy with the Atacama Large Millimeter/submillimeter Array (ALMA). We have compared the HDO line luminosity (L (HDO)) measured toward the LMC hot cores to those observed toward a sample of 17 Galactic hot cores covering three orders of magnitude in L (HDO), four orders of magnitude in bolometric luminosity (L (bol)), and a wide range of Galactocentric distances (thus metallicities). The observed values of L (HDO) for the LMC hot cores fit very well into the L (HDO) trends with L (bol) and metallicity observed toward the Galactic hot cores. We have found that L (HDO) seems to be largely dependent on the source luminosity, but metallicity also plays a role. We provide a rough estimate of the H2O column density and abundance ranges toward the LMC hot cores by assuming that HDO/H2O toward the LMC hot cores is the same as that observed in the Milky Way; the estimated ranges are systematically lower than Galactic values. The spatial distribution and velocity structure of the HDO emission in N 105-2 A is consistent with HDO being the product of the low-temperature dust grain chemistry. Our results are in agreement with the astrochemical model predictions that HDO is abundant regardless of the extragalactic environment and should be detectable with ALMA in external galaxies.

We present high-resolution Karl G. Jansky Very Large Array (VLA) observations of the protostar L1527 IRS at 7 mm, 1.3 cm, and 2 cm wavelengths. We detect the edge-on dust disk at all three wavelengths and find that it is asymmetric, with the southern side of the disk brighter than the northern side. We confirm this asymmetry through analytic modeling and also find that the disk is flared at 7 mm. We test the data against models including gap features in the intensity profile, and though we cannot rule such models out, they do not provide a statistically significant improvement in the quality of fit to the data. From these fits, we can, however, place constraints on allowed properties of any gaps that could be present in the true, underlying intensity profile. The physical nature of the asymmetry is difficult to associate with physical features owing to the edge-on nature of the disk, but it could be related to spiral arms or asymmetries seen in other imaging of more face-on disks.

Context. The chemistry of sulphur-bearing species in the interstellar medium remains poorly understood, but might play a key role in the chemical evolution of star-forming regions. Aims. Coupling laboratory experiments to observations of sulphur-bearing species in different parts of star-forming regions, we aim to understand the chemical behavior of the sulphur species in cold and warm regions of protostars, and we ultimately hope to connect them. Methods. We performed laboratory experiments in which we tested the reactivity of hydrogen sulfide (H2S) on a cold substrate with hydrogen and/or carbon monoxide (CO) under different physical conditions that allowed us to determine the products from sulphur reactions using a quadrupole mass spectrometer. The laboratory experiments were complemented by observations. We observed two luminous binary sources in the Cygnus-X star-forming complex, Cygnus X-N30 and N12, covering a frequency range of 329-361 GHz at a spatial resolution of 1 '' 5 with the SubMillimeter Array (SMA). This study was complemented by a 3 mm line survey of Cygnus X-N12 covering specific frequency windows in the frequency ranges 72.0-79.8 GHz at a spatial resolution of 34 '' 0-30 '' 0 and 84.2-115.5 GHz at a spatial resolution of 29 '' 0-21 '' 0, with the IRAM-30 m single-dish telescope. Column densities and excitation temperatures were derived under the local thermodynamic equilibrium approximation. Results. We find that OCS is a direct product from H2S reacting with CO and H under cold temperatures (T < 100 K) from laboratory experiments. OCS is therefore found to be an important solid-state S-reservoir. We identify several S-species in the cold envelope of Cyg X-N12, principally organo-sulphurs (H2CS, CS, OCS, CCS, C3S, CH3SH, and HSCN). For the hot cores of Cyg X-N12 and N30, only OCS, CS and H2CS were detected. We found a difference in the S-diversity between the hot core and the cold envelope of N12, which is likely due to the sensitivity of t

Chemistry along the star- and planet-formation sequence regulates how prebiotic building blocks-carriers of the elements CHNOPS-are incorporated into nascent planetesimals and planets. Spectral line observations across the electromagnetic spectrum are needed to fully characterize interstellar CHNOPS chemistry, yet to date there are only limited astrochemical constraints at THz frequencies. Here, we highlight advances to the study of CHNOPS astrochemistry that will be possible with the Orbiting Astronomical Satellite for Investigating Stellar Systems (OASIS). OASIS is a NASA mission concept for a space-based observatory that will utilize an inflatable 14-m reflector along with a heterodyne receiver system to observe at THz frequencies with unprecedented sensitivity and angular resolution. As part of a survey of H2O and HD toward similar to 100 protostellar and protoplanetary disk systems, OASIS will also obtain statistical constraints on the emission of complex organics from protostellar hot corinos and envelopes as well as light hydrides including NH3 and H2S toward protoplanetary disks. Line surveys of high-mass hot cores, protostellar outflow shocks, and prestellar cores will also leverage the unique capabilities of OASIS to probe high-excitation organics and small hydrides, as is needed to fully understand the chemistry of these objects.

We present velocity-resolved Stratospheric Observatory for Infrared Astronomy (SOFIA)/upgrade German REceiver for Astronomy at Terahertz Frequencies observations of [O I] and [C II] lines toward a Class I protostar, L1551 IRS 5, and its outflows. The SOFIA observations detect [O I] emission toward only the protostar and [C II] emission toward the protostar and the redshifted outflow. The [O I] emission has a width of similar to 100 km s(-1) only in the blueshifted velocity, suggesting an origin in shocked gas. The [C ii] lines are narrow, consistent with an origin in a photodissociation region. Differential dust extinction from the envelope due to the inclination of the outflows is the most likely cause of the missing redshifted [O I] emission. Fitting the [O I] line profile with two Gaussian components, we find one component at the source velocity with a width of similar to 20 km s(-1) and another extremely broad component at -30 km s(-1) with a width of 87.5 km s(-1), the latter of which has not been seen in L1551 IRS 5. The kinematics of these two components resemble cavity shocks in molecular outflows and spot shocks in jets. Radiative transfer calculations of the [O I], high-J CO, and H2O lines in the cavity shocks indicate that [O I] dominates the oxygen budget, making up more than 70% of the total gaseous oxygen abundance and suggesting [O]/[H] of similar to 1.5 x 10(-4). Attributing the extremely broad [O I] component to atomic winds, we estimate an intrinsic mass-loss rate of (1.3 +/- 0.8) x 10(-6) M-circle dot yr(-1). The intrinsic mass-loss rates derived from low-J CO, [O i], and H i are similar, supporting the model of momentum-conserving outflows, where the atomic wind carries most momentum and drives the molecular outflows.