We report on the coexistence of powerful gas outflows observed in millimeter and X-ray data of the radio-loud narrow-line Seyfert 1 Galaxy IRAS 17020+4544. Thanks to the large collecting power of the ...Large Millimeter Telescope (LMT), a prominent line arising from the 12CO(1-0) transition was revealed in recent observations of this source. The complex profile is composed by a narrow double-peak line and a broad wing. While the double-peak structure may be arising in a disk of molecular material, the broad wing is interpreted as the signature of a massive outflow of molecular gas with an approximate bulk velocity of −660 km s−1. This molecular wind is likely associated to a multi-component X-ray ultra-fast outflow with velocities reaching up to ∼ 0.1c and column densities in the range 1021-23.9 cm−2 that was reported in the source prior to the LMT observations. The momentum load estimated in the two gas phases indicates that within the observational uncertainties the outflow is consistent with being propagating through the galaxy and sweeping up the gas while conserving its energy. This scenario, which has been often postulated as a viable mechanism of how active galactic nucleus (AGN) feedback takes place, has so far been observed only in ultraluminous infrared galaxy sources. IRAS 17020+4544 with bolometric and infrared luminosity, respectively, of 5 × 1044 erg s−1 and 1.05 × 1011 L appears to be an example of AGN feedback in a NLSy1 Galaxy (a low power AGN). New proprietary multi-wavelength data recently obtained on this source will allow us to corroborate the proposed hypothesis.
We present optical and near-infrared (NIR) imaging data of the radio-loud, narrow-line Seyfert 1 galaxy 1H 0323+342, which shows intense and variable gamma-ray activity discovered by the Fermi ...satellite with the Large Area Telescope. Near-infrared and optical images are used to investigate the structural properties of the host galaxy of 1H 0323+342; this together with optical spectroscopy allows us to examine its black hole mass. Based on two-dimensional (2D) multiwavelength surface-brightness modeling, we find that statistically, the best model fit is a combination of a nuclear component and a Sersic profile (n ~ 2.8). However, the presence of a disk component (with a small bulge n ~ 1.2) also remains a possibility and cannot be ruled out with the present data. Although at first glance a spiral-arm-like structure is revealed in our images, a 2D Fourier analysis of the imagery suggests that this structure corresponds to an asymmetric ring, likely associated with a recent violent dynamical interaction. We discuss our results in the context of relativistic jet production and galaxy evolution.
Extragalactic very-high-energy (VHE; E > 100 GeV) sources are unique objects to study the most powerful particle accelerators in nature, as active galactic nuclei are likely sources of ...ultra-high-energy cosmic rays. BL Lacertae blazars are the most frequent extragalactic objects found in the VHE gamma-ray catalogs. It is very difficult to estimate their redshifts, considering they have no strong enough optical spectral features, hence ∼20% of them have unknown or poorly constrained redshifts. KUV 00311-1938 is a VHE BL Lacertae blazar, with an uncertain redshift in the range of 0.5 < z < 0.98. We have obtained deep spectroscopy using Gemini and the GTC telescopes of KUV 00311-1938 and its surroundings with high signal-to-noise ratio in 2016-2017. The lack of features did not allow us to determine the spectroscopic redshift of KUV 00311-1938; nevertheless, we obtain a lower limit of z 0.475. We determined the redshifts of 41 galaxies observed in the field-of-view of the blazar and through a population study, identified three pairs and four groups consisting of 3 or 4 members with redshifts in the range z = 0.1468-0.4756. Due to the absence of a large group of galaxies, we could not associate KUV 00311-1938 with any of the groups detected.
We report on anomalously long duration (2 ms) count rate bursts following the impact of cosmic ray showers near a 7.62 cm x⊘7.62 cm LaBr3 scintillation detector at the High Altitude Water Cherenkov ...array in Mexico, previously described by Stenkin et al. (2001), and termed “neutron bursts.” The largest burst produced 198 counts within 2 ms in our LaBr3 detector. We simulate the neutron burst albedo flux (that is, secondary emissions from an extensive air shower core impacting the ground), and show that (1) the characteristic spectra and count rates are well explained by neutron absorption in the ground and (2) any cosmic ray secondary that produces neutrons, either through hadron inelastic collisions, or photoneutron production by gamma‐rays, produces the same characteristic spectra. This implies that other natural phenomena that produce downward beams of gamma‐rays, like Terrestrial gamma ray flashes, should produce a similar “neutron burst” signature from the photoneutron reactions occurring in the soil.
Plain Language Summary
When very large cosmic ray showers (CRS) impact the ground, neutrons are produced in the soil that will rattle around until they become captured by soil particles and release energetic gamma‐rays. This produces a slow explosion of particles emanating from the ground following a CRS impact, and is termed a 'neutron burst'. We present recent observations of neutron bursts from a hand held sized gamma‐ray detector at the High Altitude Water Cherenkov (HAWC) array in Mexico, that exhibit interesting spectral features (the presence of positron annihilation), and an interesting time structure (hundreds of counts within a few ms). Our simulations indicate that Terrestrial gamma‐ray flashes (TGFs, bursts of gamma‐rays associated with lightning) should also produce these neutron bursts. An implication of this work is that existing deployments of ground based TGF instruments, comprised of small gamma‐ray detectors, can additionally be used to observe signatures of large cosmic ray showers on clear days.
Key Points
We report on fairweather count rate bursts with 2 ms duration following the impact of a large cosmic ray shower near a small scintillation detector at HAWC
Simulations show that the spectra and decay time can be produced by either hadronic interactions, or photoneutron reactions from gamma‐rays
These results imply that downward TGFs could produce a similar delayed neutron signature in the soil near ground based detectors
Introduction
The SARS-CoV-2 pandemic has produced an unprecedented clinical situation, causing a direct and indirect impact on the physical and mental health of the population. In Spain, between ...March 15 and June 21 of 2020, it was decreed a home confinement that caused the interruption of the daily life of millions of people. However, there are few studies that analyze the changes produced in psychiatric care in the Emergency Department (ED).
Objectives
To analyze the changes produced in psychiatric emergencies, subanalysing paediatric population, during the first year of the pandemic (COV1/Y-COV1) compared to the previous year (NOCOV/Y-NOCOV1). To analyze the clinical features of patients attended during the lockdown period of the pandemic (LOCK) and compare it to the period of the pandemic after the lockdown (NOLOCK).
Methods
Through the registry of computerized medical records, patients who attended the psychiatric hospital emergency department between 03/01/2019 and 02/28/2021 were identified. We also identified all attendances from 15/03 to 21/06 in 2019 and in 2020 to obtain variables from the lockdown period.
Results
During period of this study, 2694 psychiatric visits made in the ED (1744 patients - 54.3% women, and 69.5% were between 25 and 64 years-), 1537 in NOCOV and 1157 in COV1. Significant differences were found between COV1 and NOCOV in sociodemographic variables, such as employment status and number of offspring. At a clinical level, in COV1, we observed an increase in attendance due to heteroaggressive behaviors, mania, insomnia and problems due to substance use. An increase in the prescription and/or modification of treatment was observed (59.3% vs 54.3%). During COV1, in terms of discharge follow-up in the month following the ED visit, telematic assistance increased (11.4% vs. 5.3%). During the period of study, 282 ED attendances were performed, 153 in Y-NOCOV and 129 in Y-COV1. At a clinical level, during Y-COV1, a decrease in attendances related to substance use was found significant. The sub-analysis carried out for LOCK and NOLOCK yields similar data to those obtained in the COV1 vs. NOCOV1 comparison. During lockdown, the face-to-face follow-up in the month following the ED was significantly lower (39,5% vs 57,1%) regarding telematic follow-up (24,4% vs 5,8%) In this period, an increase of adolescents without previous mental health follow-up was observed (44% LOCK vs. 22% NOLOCK).
Conclusions
Our work supports the hypothesis that the COVID-19 pandemic caused a change in psychiatric care in the ED. It also shows how lockdown changed the attendance in psychiatric emergencies, and also in the later community care attendance. Changes are detected in emergency care for adolescents during the pandemic compared to the previous year. Strikingly, our study does not reflect a quantitative increase in the demand. It would be of interest to continue collecting data after the time of the present project.
Disclosure of Interest
None Declared
We report on the redshift of the BL Lac object 3FGL J0909.0+2310 based on observations obtained with the OSIRIS Multi-Object Spectrograph (MOS) mounted on the 10.4-m Gran Telescopio Canarias. A ...redshift of 0.432 plus or minus 0.002 was obtained by the identification of three absorption features (Ca ii K&H and the G band) detected in the spectrum of the BL Lac host galaxy. The closest object to the BL Lac at an angular separation of 3.8 arcsec (~21 kpc at this distance) has a similar redshift of 0.431 plus or minus 0.002. This companion galaxy could be the most likely cause of the nuclear activity as postulated by studies based on more extended data sets and cosmological models. MOS allows us to study the object's neighbourhood within a field of view of approximately 7 x 2 arcmin2 and we find two small groups of galaxies at redshifts 0.28 and 0.39 which are probably not related to the activity of 3FGL J0909.0+2310.
Context.
Ground-based γ-ray astronomy is still a rather young field of research, with strong historical connections to particle physics. This is why most observations are conducted by experiments ...with proprietary data and analysis software, as is usual in the particle physics field. However, in recent years, this paradigm has been slowly shifting toward the development and use of open-source data formats and tools, driven by upcoming observatories such as the Cherenkov Telescope Array (CTA). In this context, a community-driven, shared data format (the
gamma-astro-data-format
, or GADF) and analysis tools such as
Gammapy
and
ctools
have been developed. So far, these efforts have been led by the Imaging Atmospheric Cherenkov Telescope community, leaving out other types of ground-based
γ
-ray instruments.
Aims.
We aim to show that the data from ground particle arrays, such as the High-Altitude Water Cherenkov (HAWC) observatory, are also compatible with the GADF and can thus be fully analyzed using the related tools, in this case,
Gammapy.
Methods.
We reproduced several published HAWC results using
Gammapy
and data products compliant with GADF standard. We also illustrate the capabilities of the shared format and tools by producing a joint fit of the Crab spectrum including data from six different
γ
-ray experiments.
Results.
We find excellent agreement with the reference results, a powerful confirmation of both the published results and the tools involved.
Conclusions.
The data from particle detector arrays such as the HAWC observatory can be adapted to the GADF and thus analyzed with
Gammapy.
A common data format and shared analysis tools allow multi-instrument joint analysis and effective data sharing. To emphasize this, a sample of Crab nebula event lists is made public with this paper. Because of the complementary nature of pointing and wide-field instruments, this synergy will be distinctly beneficial for the joint scientific exploitation of future observatories such as the Southern Wide-field Gamma-ray Observatory and CTA.
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