Identifying the counterpart of HESS J1858+020

HESS J1858+020 is a weak gamma-ray source that does not have any clear cataloged counterpart at any wavelengths. Recently, the source G35.6-0.4 was re-identified as a SNR. The HESS source lies towards the southern border of this remnant. The purpose of this work is to investigate the interstellar medium around the mentioned sources in order to look for possible counterparts of the very-high energy emission. Using the 13CO J=1-0 line from the Galactic Ring Survey and mid-IR data from GLIMPSE we analyze the environs of HESS J1858+020 and SNR G35.6-0.4. The 13CO data show the presence of a molecular cloud towards the southern border of SNR G35.6-0.4 and at the same distance as the remnant. This cloud is composed by two molecular clumps, one, over the SNR shell and the other located at the center of HESS J1858+020. We estimate a molecular mass and a density of ~ 5 X 10^{3} Msun and ~ 500 cm^{-3}, respectively for each clump. Considering the gamma-ray flux observed towards HESS J1858+020, we estimate that a molecular cloud with a density of at least 150 cm^{-3} could explain the very-high energy emission hadronically. Thus, we suggest that the gamma-ray emission detected in HESS J1858+020 is due to hadronic mechanism. Additionally, analyzing mid-IR emission, we find that the region is active in star formation, which could be considered as an alternative or complementary possibility to explain the very-high energy emission.Comment: 6 pages, 3 figures, accepted for publication in A&A Lette

Unveiling the circumstellar environment towards a massive young stellar object

As a continuation of a previous work, in which we found strong evidence of massive molecular outflows towards a massive star forming site, we present a new study of this region based on very high angular resolution observations with the aim of discovering the outflow driven mechanism. Using near-IR data acquired with Gemini-NIRI at the broad H- and Ks-bands, we study a region of 22" x 22" around the UCHII region G045.47+0.05, a massive star forming site at the distance of about 8 kpc. To image the source with the highest spatial resolution possible we employed the adaptative optic system ALTAIR, achieving an angular resolution of about 0.15". We discovered a cone-like shape nebula with an opening angle of about 90 degree extending eastwards the IR source 2MASS J19142564+1109283, a very likely MYSO. This morphology suggests a cavity that was cleared in the circumstellar material and its emission may arise from scattered continuum light, warm dust, and likely emission lines from shock-excited gas. The nebula, presenting arc-like features, is connected with the IR source through a jet-like structure, which is aligned with the blue shifted CO outflow found in a previous study. The near-IR structure lies ~3" north of the radio continuum emission, revealing that it is not spatially coincident with the UCHII region. The observed morphology and structure of the near-IR nebula strongly suggest the presence of a precessing jet. In this study we have resolved the circumstellar ambient (in scale of a thousand A.U.) of a distant MYSO, indeed one of the farthest cases.Comment: Accepted in A&A Letters (October 2013

Evidence, Testimony, and Trust: How the COVID-19 Pandemic is Exacerbating the Crisis of Trust in Science

In this paper, I consider an example of fast science produced in the early stages of the pandemic and the lasting effects of the study on public safety and trust in science. Due to pressures intrinsic to contemporary science and from the pandemic to produce research on COVID quickly, studies on COVID-19 that did not meet rigorous scientific standards were used to form public health policies and recommendations. I argue that the fast science produced for COVID-19, which caused many public health policies and recommendations to change throughout the pandemic, confuses the publics and erodes their trust in science

Mapping the 13CO/C18O abundance ratio in the massive star forming region G29.96-0.02

Estimating molecular abundances ratios from the direct measurement of the emission of the molecules towards a variety of interstellar environments is indeed very useful to advance in our understanding of the chemical evolution of the Galaxy, and hence of the physical processes related to the chemistry. It is necessary to increase the sample of molecular clouds, located at different distances, in which the behavior of molecular abundance ratios, such as the 13CO/C18O ratio (X), is studied in detail. We selected the well-studied high-mass star-forming region G29.96-0.02, located at a distance of about 6.2 kpc, which is an ideal laboratory to perform this kind of studies. To study the X towards this region it was used 12CO J=3-2 data obtained from COHRS, 13CO and C18O J=3-2 data from CHIMPS, and 13CO and C18O J=2-1 data retrieved from the CDS database (observed with the IRAM 30m telescope). The distribution of column densities and X throughout the molecular cloud was studied based on LTE and non-LTE methods. Values of X between 1.5 to 10.5, with an average of 5, were found, showing that, besides the dependency between X and the galactocentric distance, the local physical conditions may strongly affect this abundance ratio. We found that correlating the X map with the location of the ionized gas and dark clouds allows us to suggest in which regions the far-UV radiation stalls in dense gaseous components, and in which ones it escapes and selectively photodissociates the C18O isotope. The non-LTE analysis shows that the molecular gas has very different physical conditions, not only spatially across the cloud, but also along the line of sight. This kind of studies may represent a tool to indirectly estimate (from molecular lines observations) the degree of photodissociation in molecular clouds, which is indeed useful to study the chemistry in the interstellar medium.Comment: Accepted in A&A (July 10, 2018

A New Participation Puzzle: Public Equity Ownership Through the Financial Crisis

Using the Survey of Consumer Finances, I document a new puzzle in household portfolio choice characterized by two phenomena. First, intertemporal changes in the distribution of wealth resulted in a decrease in public equity ownership after, but not during, the financial crisis. Second, holding fixed the level of wealth over time, the participation rate temporarily increased during the crisis, then returned to pre-crisis levels. I show that these results can be explained by, and serve as strong evidence for, decreasing relative risk aversion and portfolio inertia. I discuss implications of these findings for existing models of participation, including fixed costs and background risks

Discovering a misaligned CO outflow related to the red MSX source G034.5964-01.0292

The red MSX source G034.5964-01.0292 (MSXG34), catalogued as a massive YSO, was observed in molecular lines with the aim of discover and study molecular outflows. We mapped a region of 3'x3' centered at MSXG34 using the Atacama Submillimeter Telescope Experiment in the 12CO J=3-2 and HCO+ J=4-3 lines with an angular and spectral resolution of 22" and 0.11 km/s, respectively. Additionally, public 13CO J=1-0 and near-IR UKIDSS data obtained from the Galactic Ring Survey and the WFCAM Sciencie Archive, respectively, were analyzed. We found that the 12CO spectra towards the YSO present a self-absorption dip, as it is usual in star forming regions, and spectral wings evidencing outflow activity. The HCO+ was detected only towards the MSXG34 position at v_LSR ~ 14.2 km/s, in coincidence with the 12CO absorption dip and approximately with the velocity of previous ammonia observations. HCO+ and NH3 are known to be enhanced in molecular outflows. Analyzing the spectral wings of the 12CO line, we discovered misaligned red- and blue-shifted molecular outflows associated with MSXG34. The near-IR emission shows a cone-like shape nebulosity composed by two arc-like features related to the YSO, which can be due to a cavity cleared in the circumstellar material by a precessing jet. This can explain the misalignment in the molecular outflows. From the analysis of the 13CO J=1--0 data we suggest that the YSO is very likely related to a molecular clump ranging between 10 and 14 km/s. This suggests that MSXG34, with an associated central velocity of about 14 km/s, may be located in the background of this clump. Thus, the blue-shifted outflow is probably deflected by the interaction with dense gas along the line of sight.Comment: Accepted in A&A June 10, 201

The Particular Effects of Political and Legal Circumstances on State Markets for Firearms

This paper uses publicly available commercial data to determine how the political and legal circumstances of a state influence the production and consumption of firearms. Regression analyses are conducted using data on manufacturers and retailers. The paper finds a statistically significant relationship between the per capita number of establishments and the 2016 presidential vote share in a given state. From this analysis, Vermont is identified as an outlier for retailers and is examined as a case study. The deviation of Vermont from the general relationship establishes two findings: first, that legal protections can insulate retailers from regulation and political risk, bolstering commercial activity; and second, that such legal protections can create a positive consumption culture around guns, supporting demand. In concluding, the paper emphasizes the significance of the findings as they relate to the distinction between regulation and political climate. This study is a starting point for further research on firearm market dynamics and regulation