We report on the analysis of 436.1 hrs of nearly continuous high-speed photometry on the pulsating DB white dwarf GD358 acquired with the Whole Earth Telescope (WET) during the 2006 international observing run, designated XCOV25. The Fourier transform (FT) of the light curve contains power between 1000 to 4000 µHz, with the dominant peak at 1234 µHz. We find 27 independent frequencies distributed in 10 modes, as well as numerous combination frequencies. Our discussion focuses on a new asteroseismological analysis of GD358, incorporating the 2006 data set and drawing on 24 years of archival observations. Our results reveal that, while the general frequency locations of the identified modes are consistent throughout the years, the multiplet structure is complex and cannot be interpreted simply as l=1 modes in the limit of slow rotation. The high k multiplets exhibit significant variability in structure, amplitude and frequency. Any identification of the m components for the high k multiplets is highly suspect. The k=9 and 8 modes typically do show triplet structure more consistent with theoretical expectations. The frequencies and amplitudes exhibit some variability, but much less than the high k modes. Analysis of the k=9 and 8 multiplet splittings from 1990 to 2008 reveal a long-term change in multiplet splittings coinciding with the 1996 sforzando event, where GD358 dramatically altered its pulsation characteristics on a timescale of hours. We explore potential implications, including the possible connections between convection and/or magnetic fields and pulsations. We suggest future investigations, including theoretical investigations of the relationship between magnetic fields, pulsation, growth rates, and convection.

We present BVRI and unfiltered (Clear) light curves of 70 stripped-envelope supernovae (SESNe), observed between 2003 and 2020, from the Lick Observatory Supernova Search (LOSS) follow-up program. Our SESN sample consists of 19 spectroscopically normal SNe Ib, two peculiar SNe Ib, six SNe Ibn, 14 normal SNe Ic, one peculiar SN Ic, ten SNe Ic-BL, 15 SNe IIb, one ambiguous SN IIb/Ib/c, and two superluminous SNe. Our follow-up photometry has (on a per-SN basis) a mean coverage of 81 photometric points (median of 58 points) and a mean cadence of 3.6 d (median of 1.2 d). From our full sample, a subset of 38 SNe have pre-maximum coverage in at least one passband, allowing for the peak brightness of each SN in this subset to be quantitatively determined. We describe our data collection and processing techniques, with emphasis toward our automated photometry pipeline, from which we derive publicly available data products to enable and encourage further study by the community. Using these data products, we derive host-galaxy extinction values through the empirical colour evolution relationship and, for the first time, produce accurate rise-time measurements for a large sample of SESNe in both optical and infrared passbands. By modeling multiband light curves, we find that SNe Ic tend to have lower ejecta masses and lower ejecta velocities than SNe Ib and IIb, but higher 56Ni masses.

We present measurements of the periods, amplitudes, and types of 74 RR Lyrae stars in the globular cluster M15 derived from Nickel 1 m telescope observations conducted at Lick Observatory in 2019 and 2020. Of these RR Lyrae stars, two were previously reported but without a determination of the period. In addition, we identify five Type II Cepheid variable stars for which we report three novel period determinations, and a further 34 stars with uncertain classifications and periods. We discuss the development and subsequent application to our data of a new python package, Period-determination and Identification Pipeline Suite (pips), based on a new adaptive free-form fitting technique to detect the periods of variable stars with a clear treatment of uncertainties.

We conclude that breathing pattern in horses with heaves is characterized by severe rib cage/abdominal asynchrony, with the rib cage motion in synchrony with flow, therefore dominating ventilation. In a subset of heaves, the abdominal compartment (diaphragm, abdominal muscles) was completely out of synchrony with flow ("abdominal paradox") despite the clinical appearance of "increased abdominal effort."

We describe the Period detection and Identification Pipeline Suite (PIPS) — a new, fast, and statistically robust platform for period detection and analysis of astrophysical time-series data. PIPSis an open-source Python package that provides various pre-implemented methods and a customisable framework for automated, robust period measurements with principled uncertainties and statistical significance calculations. In addition to detailing the general algorithm that underlies PIPS, this paper discusses one of PIPS’ central and novel features, the Fourier-likelihood periodogram, and compares its performance to existing methods. The resulting improved performance implies that one can construct deeper, larger, and more reliable sets of derived properties from various observations, including all-sky surveys. We present a comprehensive validation of PIPSagainst artificially generated data, which demonstrates the reliable performance of our algorithm for a class of periodic variable stars (RR Lyrae stars).