9,908 research outputs found
The nucleus of 103P/Hartley 2, target of the EPOXI mission
103P/Hartley 2 was selected as the target comet for the Deep Impact extended
mission, EPOXI, in October 2007. There have been no direct optical observations
of the nucleus of this comet, as it has always been highly active when
previously observed. We aimed to recover the comet near to aphelion, to a)
confirm that it had not broken up and was in the predicted position, b) to
provide astrometry and brightness information for mission planning, and c) to
continue the characterisation of the nucleus. We observed the comet at
heliocentric distances between 5.7 and 5.5 AU, using FORS2 at the VLT, at 4
epochs between May and July 2008. We performed VRI photometry on deep stacked
images to look for activity and measure the absolute magnitude and therefore
estimate the size of the nucleus. We recovered the comet near the expected
position, with a magnitude of m_R = 23.74 \pm 0.06 at the first epoch. The
comet had no visible coma, although comparison of the profile with a stellar
one showed that there was faint activity, or possibly a contribution to the
flux from the dust trail from previous activity. This activity appears to fade
at further epochs, implying that this is a continuation of activity past
aphelion from the previous apparition rather than an early start to activity
before the next perihelion. Our data imply a nucleus radius of \le 1 km for an
assumed 4% albedo; we estimate a ~6% albedo. We measure a colour of (V-R) = 0.
26 \pm 0.09.Comment: 5 pages, 4 figures, accepted for publication in A&
Forms and Rotational States of the Nuclei of Ecliptic Comets
In this thesis I present measurements of the physical properties of the
nuclei of Jupiter Family comets (JFCs), based on time-series observations. From
the time-series photometry rotation rates and elongations were measured, and
from these constraints were placed on the bulk density and porosity of nuclei.
Multi-filter imaging was performed to enable measurement of their surface
colours. In addition, a large amount of `snap-shot' imaging was performed
during the observing runs, and taken with the time-series data is used to
measure nuclei sizes. These results are compared with other data from the
literature to study the general properties of JFC nuclei.
(Abridged)Comment: Ph.D thesis, Queen's University Belfast, Sept 2006. Full text at
http://homepage.mac.com/colinsnodgrass/FileSharing2.htm
Sexual Assault Case Processing: A Descriptive Model of Attrition and Decision Making
The outcomes of sexual assaults involving one suspect and one victim reported to the Anchorage Police Department (APD) in 2000 to 2003 were examined. Overall, 1,235 sexual assaults were reported to APD during this period, of which 1,074 involved one suspect and one victim. Data were collected on 1,052 of these cases to learn how the Alaska Department of Law disposed of these cases. Of the 1,052 cases examined, 188 (17.9%) were referred to the Department of Law, 127 were accepted for prosecution, and 111 resulted in a conviction. Clearly, the point of greatest attrition is from report to referral, with 85.2 percent of reported sexual assaults not being referred for prosecution. However, most offenders whose cases reach prosecutors are held accountable in some degree through the imposition of criminal sanctions.National Institute of Justice, Office of Justice Programs, United States Department of Justice.
Grant No. 2004-WB-GX-0003.Acknowledgements / Executive Summary / Statement of Research / Data Collection / Overview of Case Progression / Results / Conclusions and Discussion / Appendice
Sexual Assault Case Processing: A Descriptive Model of Attrition and Decision Making
Originally published in the Alaska Justice Forum 23(1): 1, 4-8 (Spring 2006).This study examined the outcomes of sexual assault cases reported to the Anchorage Police Department between January 2000 and December 2003. The data include 1,052 cases involving one suspect and one victim (85% of all reported sexual assaults). Cases and charges were tracked through the Alaska Department of Law to determine what was referred, accepted, and convicted.
* Overall, 18% of cases were referred for prosecution. The most common referred charge was a sexual assault in the first degree. Seventy-nine percent of referred charges were sexual assault charges.
* Overall, 12% of cases were accepted for prosecution. The greatest point of attrition was from report to referral. Once referred, 68% of cases were accepted for prosecution. Sixty-eight percent of charges were accepted by the Department of Law as referred. The most common reasons for not accepting a charge as referred were evidentiary reasons. The most common accepted charge was also a sexual assault in the first degree. Seventy-five percent of accepted charges were sexual assault charges.
* Overall, 11% of cases resulted in a conviction. Once accepted, 87% of cases resulted in a conviction. Although convictions were common in accepted cases, accepted charges were often dismissed. While 87% of accepted cases resulted in a conviction, 59% of accepted charges were dismissed. Ninety percent of guilty findings were a result of plea bargaining. With plea bargaining, some charges were dismissed but a conviction was still secured. Fifty-six percent of convicted charges were sexual assault charges. The most common convicted charge was for assault, followed by sexual assault in the second degree
X-shooter search for outgassing from Main Belt Comet P/2012 T1 (Pan-STARRS)
Context. Main Belt Comets are a recently identified population of minor bodies with stable asteroid-like orbits but cometary appearances. Sublimation of water ice is the most likely mechanism for their recurrent activity (i.e. dust tails and dust comae), although there has been no direct detection of gas. These peculiar objects could hold the key to the origin of water on Earth.
Aims. In this paper we present a search for the gas responsible for lifting dust from P/2012 T1 (Pan-STARRS), and review previous attempts at such measurements. To date such searches have mainly been indirect, looking for the common cometary gas CN rather than gasses related to water itself.
Methods. We use the VLT and X-shooter to search for emission from OH in the UV, a direct dissociation product of water.
Results. We do not detect any emission lines, and place an upper limit on water production rate from P/2012 T1 of 8 − 9 × 1025 molecules s−1. This is similar to limits derived from observations using the Herschel space telescope.
Conclusions. We conclude that the best current facilities are incapable of detecting water emission at the exceptionally low levels required to produce the observed activity in Main Belt Comets
Quantitative Analysis of Disparities in Juvenile Delinquency Referrals to the Fairbanks North Star Borough, FY2005-06
Minority youths in the Fairbanks North Star Borough are referred to the Alaska Division of Juvenile Justice (DJJ) for delinquent behavior at rates much higher than white youths.This report describes disproportionate minority contact with the Alaska juvenile justice system for youths referred to the Fairbanks office of the Division of Juvenile Justice during fiscal years 2005 and 2006 (July 1, 2004, to June 30, 2006). Possible sources of disproportionate minority contact are subsequently narrowed by examining the impact of race and ethnicity, gender, type of referral, and geography. By developing a detailed understanding of the scope of disproportionate minority contact, we become much better prepared to identify its causes and to develop evidence-based solutions.Alaska Division of Juvenile Justice.
National Institute of Justice.
Grant No. 2005-IJ-CX-0013.
Office of Juvenile Justice and Delinquency Prevention.
Grant No. 2001-JF-FX-0005.Index of Tables and Figures / Acknowledgements / Executive Summary / Quantitative Analysis of Disparities in Referrals / Sample and Data / Analysis / Results / Summary and Conclusions / Appendix A - Technical Notes on Relative Rate Indices / Appendix B - Technical Notes on Fisher's Exact Test / Appendix C - Technical Notes on Relative EB Rate Indices / Appendix D - Map
Sexual Assault Study: Differences by Victim's Alcohol Use
Poster originally presented to the Anchorage Police Department and the 2004 Alaska Summit on Violence Against Women.This issue of Anchorage Community Indicators Series 2, "Sexual Assault Study," describes the spatial patterning and geographical concentration of 282 sexual assaults reported to the Anchorage Police Department in 2001 by victim's alcohol use.This research was supported by Grant No. 2000-RH-CX-K039 awarded by the Bureau of Justice Statistics and by a UAA Faculty Development Grant to the second author.Data
Sexual assault densities by victim's alcohol use (maps) /
Alcohol use (by suspect) /
Victim injuries /
Age (of victim; of suspect) /
Race (of victim; of suspect) /
Location (pick-up location; assault location) /
Time to report /
Relationshi
The Development and Evaluation of a Novel Repurposing of a Peripheral Gaming Device for the Acquisition of Forces Applied to a Hydraulic Treatment Plinth
This technical note details the stages taken to create an instrumented hydraulic treatment plinth for the measurement of applied forces in the vertical axis. The modification used a widely available low-cost peripheral gaming device and required only basic construction and computer skills. The instrumented treatment plinth was validated against a laboratory grade force platform across a range of applied masses from 0.5–15 kg, mock Gr I-IV vertebral mobilisations and a dynamic response test. Intraclass correlation coefficients demonstrated poor reliability (0.46) for low masses of 0.5 kg improving to excellent for larger masses up to15 kg respectively; excellent to good reliability (0.97-0.86) for the mock mobilisations and moderate reliability (0.51) for the dynamic response test. The study demonstrates how a cheap peripheral gaming device can be repurposed so that forces applied to a hydraulic treatment plinth can be collected reliably when applied in a clinically reasoned manner
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