Infrared regulators and SCETII

We consider matching from SCETI, which includes ultrasoft and collinear particles, onto SCETII with soft and collinear particles at one loop. Keeping the external fermions off their mass shell does not regulate all IR divergences in both theories. We give a new prescription to regulate infrared divergences in SCET. Using this regulator, we show that soft and collinear modes in SCETII are sufficient to reproduce all the infrared divergences of SCETI. We explain the relationship between IR regulators and an additional mode proposed for SCETII.Comment: 9 pages. Added discussion about relationship between IR regulators and messenger mode

Spontaneous Coronary Artery Dissection

Spontaneous carotid artery dissection (SCAD) is a rare cause of myocardial infarction. It occurs more commonly in younger, female patients. SCAD is non-traumatic and non-iatrogenic. Most patients that experience SCAD do not have typical risk factors associated with CAD. Conditions that pre-dispose patients to SCAD includes postpartum status, multiparty, connective tissue disorders (Marfan, Ehlers-Danlos), systemic inflammatory conditions or hormonal therapy. Although rare, labor and delivery can be a cause of SCAD. Spontaneous coronary artery dissection is a cause of acute coronary syndrome in approximately 0.1 to 4% of cases. SCAD represents about 25% of ACS cases in women under 50.This case report involves a a 36 y.o. female with recent cesarean section that presents for chest pain. Diagnostic testing revealed an elevated troponin, elevated BNP and acute kidney injury. The patient underwent cardiac catheterization and was found to have a dissection of her coronary artery leading to acute congestive heart failure. The patient received supportive care and treatment of her CHF with improvement and eventually received stenting of her coronary artery. This case report focus on the presentation of this rare condition and discusses the recommended management.https://scholarlycommons.henryford.com/merf2020caserpt/1072/thumbnail.jp

Near-Infrared Counterparts to Chandra X-ray Sources toward the Galactic Center. I. Statistics and a Catalog of Candidates

We present a catalog of 5184 candidate infrared counterparts to X-ray sources detected towards the Galactic center. The X-ray sample contains 9017 point sources detected in this region by the Chandra X-ray Observatory, including data from a recent deep survey of the central 2 x 0.8 deg of the Galactic plane. A total of 6760 of these sources have hard X-ray colors, and the majority of them lie near the Galactic center, while most of the remaining 2257 soft X-ray sources lie in the foreground. We cross-correlated the X-ray source positions with the 2MASS and SIRIUS near-infrared catalogs, which collectively contain stars with a 10-sigma limiting flux of K_s<=15.6 mag. In order to distinguish absorbed infrared sources near the Galactic center from those in the foreground, we defined red and blue sources as those which have H-K_s>=0.9 and <=0.9 mag, respectively. We find that 5.8(1.5)% of the hard X-ray sources have real infrared counterparts, of which 228(99) are red and 166(27) are blue. The red counterparts are probably comprised of WR/O stars, HMXBs, and symbiotics near the Galactic center. We also find that 39.4(1.0)% of the soft X-ray sources have blue infrared counterparts; most of these are probably coronally active dwarfs in the foreground. There is a noteworthy collection of ~20 red counterparts to hard X-ray sources near the Sagittarius-B H II region, which are probably massive binaries that have formed within the last several Myr. For each of the infrared matches to X-ray sources in our catalog we derived the probability that the association is real, based on the results of the cross-correlation analysis. The catalog will serve spectroscopic surveys to identify infrared counterparts to X-ray sources near the Galactic center.Comment: Submitted to ApJ January 16, 2009; accepted July 21, 2009; 30 pages, 6 figure

Massive Stellar X-ray Sources in the Galactic Center

We present results of a spectroscopic survey of bright near-infrared counterparts to X-ray point sources from a deep Chandra survey of the Galactic nuclear bulge. K-band spectroscopy has revealed 13 new Wolf-Rayet and O-supergiant counterparts to Chandra sources in the Galactic center (GC). Although they are systematically softer in X-rays than the general GC source population of accretion powered cataclysmic variables (CVs), their X-ray colors indicate a hard component consistent with emission from plasmas with E > 2 keV. Such hard X-ray emission is not ubiquitous among single Wolf-Rayet and O stars, but is common among Wolf-Rayet+OB binaries with colliding supersonic winds. Although we regard colliding-wind binary hypothesis as the most likely scenario, it remains possible that several of these objects are wind-accreting neutron stars or black holes in supergiant high-mass X-ray binaries, or extraordinary single stars emitting hard X-rays

Summertime cyclones over the Great Lakes Storm Track from 1860–2100: variability, trends, and association with ozone pollution

Prior work indicates that the frequency of summertime mid-latitude cyclones tracking across the Great Lakes Storm Track (GLST, bounded by: 70° W, 90° W, 40° N, and 50° N) are strongly anticorrelated with ozone (O₃) pollution episodes over the Northeastern United States (US). We apply the MAP Climatology of Mid-latitude Storminess (MCMS) algorithm to 6-hourly sea level pressure fields from over 2500 yr of simulations with the GFDL CM3 global coupled chemistry-climate model. These simulations include (1) 875 yr with constant 1860 emissions and forcings (Pre-industrial Control), (2) five ensemble members for 1860–2005 emissions and forcings (Historical), and (3) future (2006–2100) scenarios following the Representative Concentration Pathways (RCP 4.5 and RCP 8.5) and a sensitivity simulation to isolate the role of climate warming from changes in O₃ precursor emissions (RCP 4.5*). The GFDL CM3 Historical simulations capture the mean and variability of summertime cyclones traversing the GLST within the range determined from four reanalysis datasets. Over the 21st century (2006–2100), the frequency of summertime mid-latitude cyclones in the GLST decreases under the RCP 8.5 scenario and in the RCP 4.5 ensemble mean. These trends are significant when assessed relative to the variability in the Pre-industrial Control simulation. In addition, the RCP 4.5* scenario enables us to determine the relationship between summertime GLST cyclones and high-O₃ events (> 95th percentile) in the absence of emission changes. The summertime GLST cyclone frequency explains less than 10% of the variability in high-O₃ events over the Northeastern US in the model, implying that other factors play an equally important role in determining high-O₃ events