SN2010jp (PTF10aaxi): A Jet-Driven Type II Supernova

We present photometry and spectroscopy of the peculiar TypeII supernova (SN) 2010jp, also named PTF10aaxi. The light curve exhibits a linear decline with a relatively low peak absolute magnitude of only -15.9, and a low radioactive decay luminosity at late times that suggests a nickel mass below 0.003 $M_{\odot}$. Spectra of SN2010jp display an unprecedented triple-peaked H$\alpha$ line profile, showing: (1) a narrow (800 km/s) central component that suggests shock interaction with dense CSM; (2) high-velocity blue and red emission features centered at -12600 and +15400 km/s; and (3) broad wings extending from -22000 to +25000 km/s. These features persist during 100 days after explosion. We propose that this line profile indicates a bipolar jet-driven explosion, with the central component produced by normal SN ejecta and CSM interaction at mid latitudes, while the high-velocity bumps and broad line wings arise in a nonrelativistic bipolar jet. Two variations of the jet interpretation seem plausible: (1) A fast jet mixes 56Ni to high velocities in polar zones of the H-rich envelope, or (2) the reverse shock in the jet produces blue and red bumps in Balmer lines when a jet interacts with dense CSM. Jet-driven SNeII are predicted for collapsars resulting from a wide range of initial masses above 25 $M_{\odot}$ at sub-solar metallicity. This seems consistent with the SN host environment, which is either an extremely low-luminosity dwarf galaxy or very remote parts of an interacting pair of star-forming galaxies. It also seems consistent with the low 56Ni mass that may accompany black hole formation. We speculate that the jet survives to produce observable signatures because the star's H envelope was mostly stripped away by previous eruptive mass loss.Comment: 11 pages, 9 figures, submitted to MNRA

Swift J2058.4+0516: Discovery of a Possible Second Relativistic Tidal Disruption Flare?

We report the discovery by the Swift hard X-ray monitor of the transient source Swift J2058.4+0516 (Sw J2058+05). Our multi-wavelength follow-up campaign uncovered a long-lived (duration >~ months), luminous X-ray (L_X,iso ~ 3 x 10^47 erg s^-1) and radio (nu L_nu,iso ~ 10^42 erg s^-1) counterpart. The associated optical emission, however, from which we measure a redshift of 1.1853, is relatively faint, and this is not due to a large amount of dust extinction in the host galaxy. Based on numerous similarities with the recently discovered GRB 110328A / Swift J164449.3+573451 (Sw J1644+57), we suggest that Sw J2058+05 may be the second member of a new class of relativistic outbursts resulting from the tidal disruption of a star by a supermassive black hole. If so, the relative rarity of these sources (compared with the expected rate of tidal disruptions) implies that either these outflows are extremely narrowly collimated (theta < 1 degree), or only a small fraction of tidal disruptions generate relativistic ejecta. Analogous to the case of long-duration gamma-ray bursts and core-collapse supernovae, we speculate that rapid spin of the black hole may be a necessary condition to generate the relativistic component. Alternatively, if powered by gas accretion (i.e., an active galactic nucleus [AGN]), Sw J2058+05 would seem to represent a new mode of variability in these sources, as the observed properties appear largely inconsistent with known classes of AGNs capable of generating relativistic jets (blazars, narrow-line Seyfert 1 galaxies).Comment: Minor typos correcte

An Optically Dark GRB Observed by HETE-2: GRB 051022

GRB 051022 was detected at 13:07:58 on 22 October 2005 by HETE-2. The location of GRB 051022 was determined immediately by the flight localization system. This burst contains multiple pulses and has a rather long duration of about 190 seconds. The detections of candidate X-ray and radio afterglows were reported, whereas no optical afterglow was found. The optical spectroscopic observations of the host galaxy revealed the redshift z = 0.8. Using the data derived by HETE-2 observation of the prompt emission, we found the absorption N_H = 8.8 -2.9/+3.1 x 10^22 cm^-2 and the visual extinction A_V = 49 -16/+17 mag in the host galaxy. If this is the case, no detection of any optical transient would be quite reasonable. The absorption derived by the Swift XRT observations of the afterglow is fully consistent with those obtained from the early HETE-2 observation of the prompt emission. Our analysis implies an interpretation that the absorbing medium could be outside external shock at R ~ 10^16 cm, which may be a dusty molecular cloud.Comment: 6 pages, 2 figures, accepted for publication in PASJ lette

The Synoptic All-Sky Infrared (SASIR) Survey

We are proposing to conduct a multicolor, synoptic infrared (IR) imaging survey of the Northern sky with a new, dedicated 6.5-meter telescope at San Pedro M\'artir (SPM) Observatory. This initiative is being developed in partnership with astronomy institutions in Mexico and the University of California. The 4-year, dedicated survey, planned to begin in 2017, will reach more than 100 times deeper than 2MASS. The Synoptic All-Sky Infrared (SASIR) Survey will reveal the missing sample of faint red dwarf stars in the local solar neighborhood, and the unprecedented sensitivity over such a wide field will result in the discovery of thousands of z ~ 7 quasars (and reaching to z > 10), allowing detailed study (in concert with JWST and Giant Segmented Mirror Telescopes) of the timing and the origin(s) of reionization. As a time-domain survey, SASIR will reveal the dynamic infrared universe, opening new phase space for discovery. Synoptic observations of over 10^6 supernovae and variable stars will provide better distance measures than optical studies alone. SASIR also provides significant synergy with other major Astro2010 facilities, improving the overall scientific return of community investments. Compared to optical-only measurements, IR colors vastly improve photometric redshifts to z ~ 4, enhancing dark energy and dark matter surveys based on weak lensing and baryon oscillations. The wide field and ToO capabilities will enable a connection of the gravitational wave and neutrino universe - with events otherwise poorly localized on the sky - to transient electromagnetic phenomena.Comment: Revised version of submitted whitepaper to the "Optical and IR Astronomy from the Ground" Program Prioritization Panel of the Astro2010 Decadal Survey; 23 page

HETE-2 Observations of the X-Ray Flash XRF 040916

A long X-ray flash was detected and localized by the instruments aboard the High Energy Transient Explorer II (HETE-2) at 00:03:30 UT on 2004 September 16. The position was reported to the GRB Coordinates Network (GCN) approximately 2 hours after the burst. This burst consists of two peaks separated by 200 s, with durations of 110 s and 60 s. We have analyzed the energy spectra of the 1st and 2nd peaks observed with the Wide Field X-Ray Monitor (WXM) and the French Gamma Telescope (FREGATE). We discuss the origin of the 2nd peak in terms of flux variabilities and timescales. We find that it is most likely part of the prompt emission, and is explained by the long-acting engine model. This feature is similar to some bright X-ray flares detected in the early afterglow phase of bursts observed by the Swift satellite.Comment: 9 pages, 4 figures, Accepted for publication in PAS

The biogeomorphological life cycle of poplars during the fluvial biogeomorphological succession: a special focus on Populus nigra L.

Riverine ecosystems are recurrently rejuvenated during destructive flood events and vegetation succession starts again. Poplars (i.e. species from Populus genera) respond to hydrogeomorphological constraints, but, in turn, also influence these processes. Thus, poplar development on bare mineral substrates is not exclusively a one-way vegetative process. Reciprocal interactions and adjustments between poplar species and sediment dynamics during their life cycle lead to the emergence of biogeomorphological entities within the fluvial corridor, such as vegetated islands, benches and floodplains. Based on a review of geomorphological, biological and ecological literature, we have identified and described the co-constructing processes between riparian poplars and their fluvial environment. We have explored the possibility that the modification of the hydrogeomorphological environment exerted, in particular, by the European black poplar (Populus nigra L.), increases its fitness and thus results in positive niche construction. We focus on the fundamental phases of dispersal, recruitment and establishment until sexual maturity of P. nigra by describing the hierarchy of interactions and the pattern of feedbacks between biotic and abiotic components. We explicitly relate the biological life cycle of P. nigra to the fluvial biogeomorphic succession model by referring to the ‘biogeomorphological life cycle’ of P. nigra. Finally, we propose new research perspectives based on this theoretical framework

The Solar System Notification Alert Processing System (SNAPS): Design, Architecture, and First Data Release (SNAPShot1)

We present here the design, architecture, and first data release for the Solar System Notification Alert Processing System (SNAPS). SNAPS is a solar system broker that ingests alert data from all-sky surveys. At present, we ingest data from the Zwicky Transient Facility (ZTF) public survey, and we will ingest data from the forthcoming Legacy Survey of Space and Time (LSST) when it comes online. SNAPS is an official LSST downstream broker. In this paper we present the SNAPS design goals and requirements. We describe the details of our automatic pipeline processing in which the physical properties of asteroids are derived. We present SNAPShot1, our first data release, which contains 5,458,459 observations of 31,693 asteroids observed by ZTF from 2018 July to 2020 May. By comparing a number of derived properties for this ensemble to previously published results for overlapping objects we show that our automatic processing is highly reliable. We present a short list of science results, among many that will be enabled by our SNAPS catalog: (1) we demonstrate that there are no known asteroids with very short periods and high amplitudes, which clearly indicates that in general asteroids in the size range 0.3–20 km are strengthless; (2) we find no difference in the period distributions of Jupiter Trojan asteroids, implying that the L4 and L5 clouds have different shape distributions; and (3) we highlight several individual asteroids of interest. Finally, we describe future work for SNAPS and our ability to operate at LSST scale

Cyclones and skinny dolphins: adaptation pathways for Pacific communities under rapid global change

The Pacific region is experiencing accelerating global change with complex interactions amongst multiple drivers, yet the onus for urgent adaptation falls largely on communities. Proponents of adaptation must therefore ensure that communities are empowered and enabled to design and implement their own adaptation plans after project cycles have concluded, and that this capacity is scaled beyond the original focus. To address this challenge, we tested a new approach in the Solomon Islands for the iterative development, implementation and evaluation of community-led adaptation. Our theory of change was that by co-designing a decision-making process with a network of community facilitators, livelihood adaptation planning could be mainstreamed and scaled out across rural communities. We implemented a planning process based on systems thinking, social learning and co-production, which we assessed using a novel participatory monitoring, evaluation and learning framework. The process involved six steps: (1) identifying drivers of change; (2) developing shared visions for livelihoods; (3) scoping possible futures for livelihoods; (4) identifying existing community adaptive capacity; (5) determining priority ‘no-regrets’ strategies to achieve the community vision and (6) mapping adaptation pathways of implementation decisions. Community facilitators co-designed the process, and then ran it in their communities to develop place-based adaptation pathways suited to the local decision-making context, and scaling the process out to neighbouring villages through peer-to-peer learning. Results from a monitoring, evaluation and learning assessment showed the process had generated shifts in thinking among communities towards anticipatory adaptation and the development and implementation of livelihood adaptation pathways. The process had also empowered people to have ownership, responsibility and agency for their futures without major ongoing support from outside agencies.</p