5,101 research outputs found
The Skeletal Biology of the New York African Burial Ground (Pt. 2): Burial Descriptions and Appendices
https://scholarworks.wm.edu/asbook/1039/thumbnail.jp
The Skeletal Biology of the New York African Burial Ground (Pt. 1)
The New York African Burial Ground was ârediscoveredâ in 1989 in the process of preparation for the construction of a proposed 34-story federal office building by the U.S. General Services Administration (GSA) at 290 Broadway in New York City (Ingle et al. 1990). The site for the proposed building was once part of the African Burial Ground that extended âfrom Chambers Street on the south to Duane Street on the north and from Centre Street on the east to Broadway on the westâ (Yamin 2000:vii). A fullscale archaeological excavation was conducted by Historic Conservation and Interpretation (HCI) and John Milner Associates, Inc. (JMA), preceding the building project, as required under Section 106 of the National Historic Preservation Act of 1966 (NHPA) (as amended) in order to mitigate the destruction of potential cultural resources (Figure 1). The excavation and construction site on the African Burial Ground is located at Foley Square, in the city block bounded by Broadway, Duane, Reade, and Elk Streets in Lower Manhattan, one block north of City Hall.https://scholarworks.wm.edu/asbook/1042/thumbnail.jp
Observations of the 2019 April 4 Solar Energetic Particle Event at the Parker Solar Probe
A solar energetic particle event was detected by the Integrated Science Investigation of the Sun (ISâIS) instrument suite on Parker Solar Probe (PSP) on 2019 April 4 when the spacecraft was inside of 0.17 au and less than 1 day before its second perihelion, providing an opportunity to study solar particle acceleration and transport unprecedentedly close to the source. The event was very small, with peak 1 MeV proton intensities of ~0.3 particles (cmÂČ sr s MeV)â»Âč, and was undetectable above background levels at energies above 10 MeV or in particle detectors at 1 au. It was strongly anisotropic, with intensities flowing outward from the Sun up to 30 times greater than those flowing inward persisting throughout the event. Temporal association between particle increases and small brightness surges in the extreme-ultraviolet observed by the Solar TErrestrial RElations Observatory, which were also accompanied by type III radio emission seen by the Electromagnetic Fields Investigation on PSP, indicates that the source of this event was an active region nearly 80° east of the nominal PSP magnetic footpoint. This suggests that the field lines expanded over a wide longitudinal range between the active region in the photosphere and the corona
Energetic Particle Increases Associated with Stream Interaction Regions
The Parker Solar Probe was launched on 2018 August 12 and completed its second orbit on 2019 June 19 with perihelion of 35.7 solar radii. During this time, the Energetic Particle Instrument-Hi (EPI-Hi, one of the two energetic particle instruments comprising the Integrated Science Investigation of the Sun, ISâIS) measured seven proton intensity increases associated with stream interaction regions (SIRs), two of which appear to be occurring in the same region corotating with the Sun. The events are relatively weak, with observed proton spectra extending to only a few MeV and lasting for a few days. The proton spectra are best characterized by power laws with indices ranging from â4.3 to â6.5, generally softer than events associated with SIRs observed at 1 au and beyond. Helium spectra were also obtained with similar indices, allowing He/H abundance ratios to be calculated for each event. We find values of 0.016â0.031, which are consistent with ratios obtained previously for corotating interaction region events with fast solar wind †600 km sâ»Âč. Using the observed solar wind data combined with solar wind simulations, we study the solar wind structures associated with these events and identify additional spacecraft near 1 au appropriately positioned to observe the same structures after some corotation. Examination of the energetic particle observations from these spacecraft yields two events that may correspond to the energetic particle increases seen by EPI-Hi earlier
Interaction of ENSO-driven Flood Variability and Anthropogenic Changes in Driving Channel Evolution: Corryong/ Nariel Creek, Australia
This is an Accepted Manuscript of an article published by Taylor & Francis in Australian Geographer on 03/09/2015, available online: 10.1080/00049182.2015.1048595Understanding the relative contributions of climatic and anthropogenic drivers of channel change are important to inform river management, especially in the context of environmental change. This global debate is especially pertinent in Australia as catchments have been severely altered since recent European settlement, and there is also strong evidence of cyclical climate variability controlling environmental systems. Corryong/Nariel Creek is an ideal setting to further study the interaction between climate and anthropogenic changes on channel evolution as it has experienced both significant periods of flood and drought, controlled by the El Niño Southern Oscillation (ENSO), and extensive anthropogenic changes. Since European settlement the floodplain has been completely cleared, the riparian zone almost entirely invaded by willows, and every reach of the channel has experienced some form of direct channel modification. Through the combined analysis of channel evolution, climate changes and anthropogenic history of the river it was found that both the ENSO-driven climate and anthropogenic drivers are significant, although at different scales of channel change. Significant straightening in response to land clearing in the early twentieth century occurred before any records of direct channel modifications. Following this, most river management works were in response to instabilities created in the clearing period, or to instabilities created by flooding triggering a new phase of instability in reaches which had already undergone stabilisation works. Overall, human activities triggered channel instability via land clearing, and management works since then generally exacerbated erosion during high flows that are driven by climate fluctuations. This research raises the interesting question of whether rivers in Australia have become more responsive to the ENSO cycle since the clearing of catchment and riparian vegetation, or whether the past response to climate variability was different
Energetic Particle Observations from the Parker Solar Probe Using Combined Energy Spectra from the ISâIS Instrument Suite
The Integrated Science Investigations of the Sun (ISâIS) instrument suite includes two Energetic Particle instruments: EPI-Hi, designed to measure ions from ~1 to 200 MeV nucâ»Âč, and EPI-Lo, designed to measure ions from ~20 to ~15 MeV nucâ»Âč. We present an analysis of eight energetic proton events observed across the energy range of both instruments during Parker Solar Probe's (PSP) first two orbits in order to examine their combined energy spectra. Background corrections are applied to help resolve spectral breaks between the two instruments and are shown to be effective. In doing so we demonstrate that even in the early stages of calibration, ISâIS is capable of producing reliable spectral observations across broad energy ranges. In addition to making groundbreaking measurements very near the Sun, ISâIS also characterizes energetic particle populations over a range of heliocentric distances inside 1 au. During the first two orbits, ISâIS observed energetic particle events from a single corotating interaction region (CIR) at three different distances from the Sun. The events are separated by two Carrington rotations and just 0.11 au in distance; however, the relationship shown between proton intensities and proximity of the spacecraft to the source region shows evidence of the importance of transport effects on observations of energetic particles from CIRs. Future ISâIS observations of similar events over larger distances will help disentangle the effects of CIR-related acceleration and transport. We apply similar spectral analyses to the remaining five events, including four that are likely related to stream interaction regions (SIRs) and one solar energetic particle (SEP) event
Energetic Particle Observations from Parker Solar Probe using Combined Energy Spectra from the ISIS Instrument Suite
The Integrated Science Investigations of the Sun (ISIS) instrument
suite includes two Energetic Particle instruments: EPI-Hi, designed to measure
ions from ~1-200 MeV/nuc, and EPI-Lo, designed to measure ions from ~20 keV/nuc
to ~15 MeV/nuc. We present an analysis of eight energetic proton events
observed across the energy range of both instruments during PSP's first two
orbits in order to examine their combined energy spectra. Background
corrections are applied to help resolve spectral breaks between the two
instruments and are shown to be effective. In doing so we demonstrate that,
even in the early stages of calibration, ISIS is capable of producing
reliable spectral observations across broad energy ranges. In addition to
making groundbreaking measurements very near the Sun, ISIS also
characterizes energetic particle populations over a range of heliocentric
distances inside 1 au. During the first two orbits, ISIS observed
energetic particle events from a single corotating interaction region (CIR) at
three different distances from the Sun. The events are separated by two
Carrington rotations and just 0.11 au in distance, however the relationship
shown between proton intensities and proximity of the spacecraft to the source
region shows evidence of the importance of transport effects on observations of
energetic particles from CIRs. Future ISIS observations of similar
events over larger distances will help disentangle the effects of CIR-related
acceleration and transport. We apply similar spectral analyses to the remaining
five events, including four that are likely related to stream interaction
regions (SIRs) and one solar energetic particle (SEP) event.Comment: Accepted for publication in the Astrophysical Journal Supplement
Serie
Determination of the Michel Parameters and the tau Neutrino Helicity in tau Decay
Using the CLEO II detector at the storage ring CESR, we have
determined the Michel parameters , , and in decay as well as the tau neutrino helicity parameter
in decay. From a data sample of
tau pairs produced at , using events of
the topology and , and the determined sign of , the combined
result of the three samples is: , , , and
. The results are in agreement with
the Standard Model V-A interaction.Comment: 18 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Study of e+e- --> pi+ pi- pi0 process using initial state radiation with BABAR
The process e+e- --> pi+ pi- pi0 gamma has been studied at a center-of-mass
energy near the Y(4S) resonance using a 89.3 fb-1 data sample collected with
the BaBar detector at the PEP-II collider. From the measured 3pi mass spectrum
we have obtained the products of branching fractions for the omega and phi
mesons, B(omega --> e+e-)B(omega --> 3pi)=(6.70 +/- 0.06 +/- 0.27)10-5 and
B(phi --> e+e-)B(phi --> 3pi)=(4.30 +/- 0.08 +/- 0.21)10-5, and evaluated the
e+e- --> pi+ pi- pi0 cross section for the e+e- center-of-mass energy range
1.05 to 3.00 GeV. About 900 e+e- --> J/psi gamma --> pi+ pi- pi0 gamma events
have been selected and the branching fraction B(J/psi --> pi+ pi- pi0)=(2.18
+/- 0.19)% has been measured.Comment: 21 pages, 37 postscript figues, submitted to Phys. Rev.
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