322 research outputs found
Positive Coping among Wives of Male Christian Clergy
Clergy spouses experience various life stressors, yet many cope and function effectively in the midst of their daily challenges. Mental health professionals were asked to identify wives of male clergy who exemplify emotional and spiritual health. Nominees were contacted and interviews conducted with 25 women. Each interviewee was asked about coping with normal life stressors, stressors associated with being married to a minister, and catastrophic life events. All interviews were transcribed and coded, using grounded theory. Participants emphasized the importance of spirituality, social support, limit-setting, and healthy lifestyle choices. Implications are discussed
Self-Dual Conformal Supergravity and the Hamiltonian Formulation
In terms of Dirac matrices the self-dual and anti-self-dual decomposition of
a conformal supergravity is given and a self-dual conformal supergravity theory
is developed as a connection dynamic theory in which the basic dynamic variabes
include the self-dual spin connection i.e. the Ashtekar connection rather than
the triad. The Hamiltonian formulation and the constraints are obtained by
using the Dirac-Bergmann algorithm.
PACS numbers: 04.20.Cv, 04.20.Fy,04.65.+
Very High Energy Gamma-Ray Emission from the Blazar Markarian 421
Very high energy gamma-ray emission from the BL Lac object Markarian 421 has
been detected over three observing seasons on 59 nights between April 1992 and
June 1994 with the Whipple 10-meter imaging Cherenkov telescope. During its
initial detection in 1992, its flux above 500 GeV was
1.610photons cm s. Observations in 1993 confirmed
this level of emission. For observations made between December 1993 and April
1994, its intensity was a factor of 2.20.5 lower. Observations on 14 and
15 May, 1994 showed an increase over this quiescent level by a factor of
10 (Kerrick et al. 1995). This strong outburst suggests that 4 episodes
of increased flux measurements on similar time scales in 1992 and 1994 may be
attributed to somewhat weaker outbursts. The variability of the TeV gamma-ray
emission from Markarian 421 stands in contrast to EGRET observations (Lin et
al. 1994) which show no evidence for variability.Comment: gzip compressed tar file including LaTeX text and 4 postscript
figures (14 pages total incl. 4 tables), accepted for publication in the
Astrophysical Journal. Contact address is [email protected]
BL Lac Objects in the Synchrotron Proton Blazar Model
We calculate the spectral energy distribution (SED) of electromagnetic
radiation and the spectrum of high energy neutrinos from BL Lac objects in the
context of the Synchrotron Proton Blazar Model. In this model, the high energy
hump of the SED is due to accelerated protons, while most of the low energy
hump is due to synchrotron radiation by co-accelerated electrons. To accelerate
protons to sufficiently high energies to produce the high energy hump, rather
high magnetic fields are required. Assuming reasonable emission region volumes
and Doppler factors, we then find that in low-frequency peaked BL Lacs (LBLs),
which have higher luminosities than high-frequency peaked BL Lacs (HBLs), there
is a significant contribution to the high frequency hump of the SED from pion
photoproduction and subsequent cascading, including synchrotron radiation by
muons. In contrast, in HBLs we find that the high frequency hump of the SED is
dominated by proton synchrotron radiation. We are able to model the SED of
typical LBLs and HBLs, and to model the famous 1997 flare of Markarian 501. We
also calculate the expected neutrino output of typical BL Lac objects, and
estimate the diffuse neutrino intensity due to all BL Lacs. Because pion
photoproduction is inefficient in HBLs, as protons lose energy predominantly by
synchrotron radiation, the contribution of LBLs dominates the diffuse neutrino
intensity. We suggest that nearby LBLs may well be observable with future
high-sensitivity TeV gamma-ray telescopes.Comment: 33 pages, 20 Figures. Astropart. Phys., accepte
The Gamma Ray Detection Capabilities of the Alpha Magnetic Spectrometer
The modeled performance of the Alpha Magnetic Spectrometer (AMS) as a high
energy (0.3 to 100 GeV) gamma-ray detector is described, and its gamma ray
astrophysics objectives are discussed.Comment: Latex2e file; 33 pages of text, 20 EPS figures. Accepted for
publication in Astroparticle Physics. Correction to affiliations; no
modifications of tex
On the Absorption of High Energy Gamma-Rays by Intergalactic Infrared Radiation
We present a new calculation of the intergalactic -ray
pair-production absorption coefficient as a function of both energy and
redshift up to the redshift of 3C279, z = 0.54. In reexamining this problem, we
make use of new observational data on the intergalactic infrared radiation
field (IIRF), together with recent theoretical models of the galactic spectral
energy distributions of the IIRF from stars and dust reradiation and estimates
of the IIRF from galaxy counts and {\it COBE} results. We present our results
for two fairly well defined IIRF spectral energy distributions, one of which is
within of our previous estimate of the IIRF at m.
We then apply our results to the -ray spectrum of Mrk 421, and obtain
good agreement with the observational data, including the recent results of the
{\it HEGRA} group.Comment: Plain TeX file with text in abs96.tex, 3 postscript figures (Fig. 1 -
ircobe.eps, Fig. 2 - taupl.eps, Fig. 3 - mki.eps), stylefile epsf.sty
included, accepted for publication in the Astrophysical Journa
Back-reacted saponite in Jurassic mudstones and limestones intruded by a Tertiary sill, Isle of Skye
The Lón Ostatoin stream section, Trotternish Peninsula, Isle of Skye, exposes a sequence of Middle Jurassic mudstones and limestones which have been locally metasomatized by a transgressive sill of Tertiary age. Limestones in the sequence, including some previously reported as bentonite, have been altered to an unusual assemblage of grossular garnet and saponite clay. The mudstones also contain large proportions of saponite together with pyroxene and zeolites. Saponite also occurs within the basalt intrusion. Grossular and pyroxene represent artifacts of relatively high-temperature assemblages that formed during an early phase of alteration. As the intrusion and adjacent altered country rocks cooled, lower-temperature fluids flowed through a late set of contraction (micro)fractures. Back-reacted saponite, analcime and clinoptilolite were formed, possibly as alteration products of the unstable higher-temperature minerals. The lower-temperature mineral assemblage eventually sealed the late fracture system.
This paper highlights an important concept for the study of analogue sites used to investigate thermal effects on engineered liners or barrier host rocks for the landfill and radioactive-waste industries. This is that the original thermally altered mineral assemblage may be overprinted by later, lower-temperature back-reactions. A detailed understanding of both processes is necessary in order to construct a sensible model for the thermal and mineralogical evolution of the site
Tau Neutrinos Underground: Signals of Oscillations with Extragalactic Neutrinos
The appearance of high energy tau neutrinos due to
oscillations of extragalactic neutrinos can be observed by measuring the
neutrino induced upward hadronic and electromagnetic showers and upward muons.
We evaluate quantitatively the tau neutrino regeneration in the Earth for a
variety of extragalactic neutrino fluxes. Charged-current interactions of the
upward tau neutrinos below and in the detector, and the subsequent tau decay
create muons or hadronic and electromagnetic showers. The background for these
events are muon neutrino and electron neutrino charged-current and
neutral-current interactions, where in addition to extragalactic neutrinos, we
consider atmospheric neutrinos. We find significant signal to background ratios
for the hadronic/electromagnetic showers with energies above 10 TeV to 100 TeV
initiated by the extragalactic neutrinos. We show that the tau neutrinos from
point sources also have the potential for discovery above a 1 TeV threshold. A
kilometer-size neutrino telescope has a very good chance of detecting the
appearance of tau neutrinos when both muon and hadronic/electromagnetic showers
are detected.Comment: section added and two new figs; accepted for publication in Physical
Review
Syntectonic mobility of supergene nickel ores of New Caledonia (Southwest Pacific). Evidence from faulted regolith and garnierite veins.
International audienceSupergene nickel deposits of New Caledonia that have been formed in the Neogene by weathering of obducted ultramafic rocks are tightly controlled by fracture development. The relationship of tropical weathering and tectonic structures, faults and tension gashes, have been investigated in order to determine whether fractures have play a passive role only, as previously thought; or alternatively, if brittle tectonics was acting together with alteration. From the observation of time-relationship, textures, and mineralogy of various fracture fills and fault gouges, it may be unambiguously established that active faulting has play a prominent role not only in facilitating drainage and providing room for synkinematic crystallisation of supergene nickel silicate, but also in mobilising already formed sparse nickel ore, giving birth to the very high grade ore nicknamed "green gold"
Back-reacted saponite in Jurassic mudstones and limestones intruded by a Tertiary sill, Isle of Skye
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