The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was created by adding polarimetric capability to the BLAST experiment that was flown in 2003, 2005, and 2006. ...BLASTPol inherited BLAST's 1.8 m primary and its Herschel/SPIRE heritage focal plane that allows simultaneous observation at 250, 350, and 500 mum. We flew BLASTPol in 2010 and again in 2012. Both were long duration Antarctic flights. Here we present polarimetry of the nearby filamentary dark cloud Lupus I obtained during the 2010 flight. Despite limitations imposed by the effects of a damaged optical component, we were able to clearly detect submillimeter polarization on degree scales. We compare the resulting BLASTPol magnetic field map with a similar map made via optical polarimetry. (The optical data were published in 1998 by J. Rizzo and collaborators.) The two maps partially overlap and are reasonably consistent with one another. We compare these magnetic field maps to the orientations of filaments in Lupus I, and we find that the dominant filament in the cloud is approximately perpendicular to the large-scale field, while secondary filaments appear to run parallel to the magnetic fields in their vicinities. This is similar to what is observed in Serpens South via near-IR polarimetry, and consistent with what is seen in MHD simulations by F. Nakamura and Z. Li.
We present 450- and 850-μm maps of R Coronae Australis. We compare the maps with previous surveys of the region, and shed new light on the previously unknown nature of the protostellar sources at the ...centre of the cloud. We clarify the nature of two millimetre sources previously discovered in lower-resolution data. We identify one new Class 0 protostar, which we label SMM 1B, and we measure the envelope masses of a number of more evolved protostars. We identify two new pre-stellar cores, which we call SMM 1A and SMM 6.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Reverberation chamber measurements typically rely upon spatially averaged squared pressure for the calculation of sound absorption, sound power, and other acoustic values. While a reverberation ...chamber can provide an approximately diffuse sound field, variations in sound pressure consistently produce uncertainty in measurement results. This paper explores the benefits of using total energy density or squared particle velocity magnitude (kinetic energy density) instead of squared pressure (potential energy density) for sound absorption and sound power measurements. The approaches are based on methods outlined in current ISO standards. The standards require a sufficient number of source-receiver locations to obtain suitable measurement results. The total and kinetic energy densities exhibit greater spatial uniformity at most frequencies than potential energy density, thus requiring fewer source-receiver positions to produce effective results. Because the total energy density is typically the most uniform of the three quantities at low frequencies, its use could also impact the usable low-frequency ranges of reverberation chambers. In order to employ total and kinetic energy densities for sound absorption measurements, relevant energy-based impulse responses were developed as part of the work for the assessment of sound field decays.
Summary
We present an r‐package, stagePop, which is a tool for predicting the deterministic dynamics and interactions of stage‐structured populations (i.e. where the life cycle consists of distinct ...stages, for example eggs, juveniles and reproductive adults).
The continuous‐time formulation enables stagePop to easily simulate time‐varying stage durations, overlapping generations and density‐dependent vital rates.
The package can be used to predict predator–prey interactions, host–parasitoid interactions, resource competition, intra‐specific competition and the effects of environmental change on stage‐structured (and non‐stage structured) species.
It can be used for predicting the effects of bio‐control and climate change, investigating mechanisms for maintaining diversity, predicting the dynamics of complex food webs following perturbation and so on.
The code is based on the formulation by Nisbet and Gurney (Theoretical Population Biology, 23, 1983, 114) using delay‐differential equations, which are solved using the r‐packages deSolve or PBSddesolve.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We present observations of the Auriga-CaliforniaMolecular Cloud (AMC) at 3.6, 4.5, 5.8, 8.0, 24, 70, and 160 mum observed with the IRAC and MIPS detectors as part of the Spitzer Gould Belt Legacy ...Survey. The total mapped areas are 2.5 deg super(2) with IRAC and 10.47 deg super(2) with MIPS. This giant molecular cloud is one of two in the nearby Gould Belt of star-forming regions, the other being the Orion A Molecular Cloud (OMC). We compare source counts, colors, and magnitudes in our observed region to a subset of the SWIRE data that was processed through our pipeline. Using color-magnitude and color-color diagrams, we find evidence for a substantial population of 166 young stellar objects (YSOs) in the cloud, many of which were previously unknown. Most of this population is concentrated around the LkHalpha 101 cluster and the filament extending from it.We present a quantitative description of the degree of clustering and discuss the relative fraction of YSOs in earlier (Class I and F) and later (Class II) classes compared to other clouds.We perform simple SED modeling of the YSOs with disks to compare the mid-IR properties to disks in other clouds and identify 14 classical transition disk candidates. Although the AMC is similar in mass, size, and distance to the OMC, it is forming about 15-20 times fewer stars.
Subjects with chronic fatigue syndrome (CFS) frequently report symptoms of subnormal body temperature and low-grade fever. We conducted a study to determine whether CFS subjects manifest any ...abnormality of core body temperature (CBT) that might help explain their fatigue.
Continuous 24-hour recordings of CBT measured every 5 min were performed in 7 subjects meeting the Centers for Disease Control definition of CFS. Three additional groups were studied: normal controls, subjects with seasonal allergy, and subjects with major depression. Subjects (n = 7) in each group were age-, sex-, and weight-matched to the CFS group and had normal basal metabolic rates, thyroid function, and 24-hour urinary free cortisol excretions. CTB was measured with an ingestible radio frequency transmitter pill and a belt-worn receiver-logger. Each pill was factory-calibrated to ± 0.1°C and field-calibrated with a water bath calibration prior to use.
The 24-hour mean calibration-adjusted CBTs of each group were not significantly different (control: 37.00 ± 0.17°C; CFS: 37.04 ± 0.31°C; allergy: 37.15 ± 0.18°C; depression: 37.16 ± 0.18°C). Similarly, the mean peak and trough circadian temperatures were not statistically different. The mean 24-hour profile of CBT for each group showed a similar circadian rhythm. In simultaneously collected blood samples, each group showed a similar circadian profile of serum cortisol with a peak occurring at 08:00.
Subjects with CFS have normal CBT despite frequent self-reports of subnormal body temperature and low-grade fever.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A cryogenic achromatic half-wave plate (HWP) for submillimetre astronomical polarimetry has been designed, manufactured, tested and deployed in the Balloon-borne Large-Aperture Submillimeter ...Telescope for Polarimetry (BLASTPol). The design is based on the five-slab Pancharatnam recipe and it works in the wavelength range 200-600 μm, making it the broadest-band HWP built to date at (sub)millimetre wavelengths. The frequency behaviour of the HWP has been fully characterized at room and cryogenic temperatures with incoherent radiation from a polarizing Fourier transform spectrometer. We develop a novel empirical model, complementary to the physical and analytical ones available in the literature, that allows us to recover the HWP Mueller matrix and phase shift as a function of frequency and extrapolated to 4 K. We show that most of the HWP non-idealities can be modelled by quantifying one wavelength-dependent parameter, the position of the HWP equivalent axes, which is then readily implemented in a map-making algorithm. We derive this parameter for a range of spectral signatures of input astronomical sources relevant to BLASTPol, and provide a benchmark example of how our method can yield improved accuracy on measurements of the polarization angle on the sky at submillimetre wavelengths.
Turbulence and magnetic fields are expected to be important for regulating molecular cloud formation and evolution. However, their effects on sub-parsec to 100 parsec scales, leading to the formation ...of starless cores, are not well understood. We investigate the prestellar core structure morphologies obtained from analysis of the Herschel-SPIRE 350 mu m maps of the Lupus I cloud. This distribution is first compared on a statistical basis to the large-scale shape of the main filament. We find the distribution of the elongation position angle of the cores to be consistent with a random distribution, which means no specific orientation of the morphology of the cores is observed with respect to the mean orientation of the large-scale filament in Lupus I, nor relative to a large-scale bent filament model. This distribution is also compared to the mean orientation of the large-scale magnetic fields probed at 350 mu m with the Balloon-borne Large Aperture Telescope for Polarimetry during its 2010 campaign. Here again we do not find any correlation between the core morphology distribution and the average orientation of the magnetic fields on parsec scales. Our main conclusion is that the local filament dynamics-including secondary filaments that often run orthogonally to the primary filament-and possibly small-scale variations in the local magnetic field direction, could be the dominant factors for explaining the final orientation of each core.
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