Strong late-time circumstellar interaction in the peculiar supernova iPTF14hls

We present a moderate-resolution spectrum of the peculiar Type II supernova iPTF14hls taken on day 1153 after discovery. This spectrum reveals the clear signature of shock interaction with dense circumstellar material (CSM). We suggest that this CSM interaction may be an important clue for understanding the extremely unusual photometric and spectroscopic evolution seen over the first 600 days of iPTF14hls. The late-time spectrum shows a double-peaked intermediate-width H-alpha line indicative of expansion speeds around 1000 km/s, with the double-peaked shape hinting at a disc-like geometry in the CSM. If the CSM was highly asymmetric, perhaps in a disc or torus that was ejected from the star 3-6 years prior to explosion, then the CSM interaction could have been overrun and hidden below the SN ejecta photosphere from a wide range of viewing angles. In that case, CSM interaction luminosity would have been thermalized well below the photosphere, possibly sustaining the high luminosity without exhibiting the traditional observational signatures of strong CSM interaction (narrow H-alpha emission and X-rays). Variations in density structure of the CSM could account for the multiple rebrightenings of the lightcurve. We propose that enveloped CSM interaction as seen in some recent SNe, rather than an entirely new explosion mechanism, may be adequate to explain the peculiar evolution of iPTF14hls.Comment: 6 pages, 5 figures, submitted to MNRAS with referee respons

Massive stars dying alone: The extremely remote environment of SN 2009ip

We present late-time HST images of the site of supernova (SN) 2009ip taken almost 3 yr after its bright 2012 luminosity peak. SN 2009ip is now slightly fainter in broad filters than the progenitor candidate detected by HST in 1999. The current source continues to be dominated by ongoing late-time CSM interaction that produces strong H-alpha emission and a weak pseudo-continuum, as found previously for 1-2 yr after explosion. The intent of these observations was to search for evidence of recent star formation in the local (1kpc; 10 arcsec) environment around SN 2009ip, in the remote outskirts of its host spiral galaxy NGC 7259. We can rule out the presence of any massive star-forming complexes like 30 Dor or the Carina Nebula at the SN site or within a few kpc. If the progenitor of SN 2009ip was really a 50-80 Msun star as archival HST images suggested, then it is strange that there is no sign of this type of massive star formation anywhere in the vicinity. A possible explanation is that the progenitor was the product of a merger or binary mass transfer, rejuvenated after a lifetime that was much longer than 4-5 Myr, allowing its natal H II region to have faded. A smaller region like the Orion Nebula would be an unresolved but easily detected point source. This is ruled out within 1.5 kpc around SN 2009ip, but a small H II region could be hiding in the glare of SN 2009ip itself. Later images after a few more years have passed are needed to confirm that the progenitor candidate is truly gone and to test for the presence of a small H II region or cluster at the SN position.Comment: 8 pages, 5 figs. submitted to MNRA

Reading The Bricklin: Narrating the Place of Dreaming in an Era of Self-Sufficiency

The Bricklin: An Automotive Fantasy traces the rise and fall of efforts to build Malcolm Bricklin’s signature sports car in rural New Brunswick in the early 1970s. I read The Bricklin as an effort by contemporary Atlantic Canadian writers and artists to highlight how the history of place shapes experience without replicating formulaic conceptions of rural life on the East Coast. Rather than subverting festishized versions of an anti-modern Atlantic Canada, The Bricklin both critiques and celebrates the nostalgic exploration of place.RésuméThe Bricklin: An Automotive Fantasy retrace l’essor et le déclin des efforts déployés pour construire la voiture de sport signée Malcolm Bricklin en région rurale du Nouveau-Brunswick dans le début des années 1970. J’ai considéré The Bricklin comme un effort des écrivains et artistes contemporains du Canada atlantique à souligner à quel point l’histoire d’une région façonne l’expérience sans pour autant se rattacher aux conceptions stéréotypées de la vie rurale de la côte Est. De fait, The Bricklin réussit à la fois à critiquer et célèbrer l’exploration nostalgique d’un endroit plutôt que de renverser des versions fétichisées d’un Canada atlantique anti-moderniste.The Bricklin: An Automotive Fantasy retrace l’essor et le déclin des efforts déployés pour construire la voiture de sport signée Malcolm Bricklin en région rurale du Nouveau-Brunswick dans le début des années 1970. J’ai considéré The Bricklin comme un effort des écrivains et artistes contemporains du Canada atlantique à souligner à quel point l’histoire d’une région façonne l’expérience sans pour autant se rattacher aux conceptions stéréotypées de la vie rurale de la côte Est. De fait, The Bricklin réussit à la fois à critiquer et célèbrer l’exploration nostalgique d’un endroit plutôt que de renverser des versions fétichisées d’un Canada atlantique anti-moderniste

Rethinking the Relevance of Magic Realism for English-Canadian Literature: Reading Ann-Marie MacDonald’s Fall On Your Knees

Canadian magic realist texts are often identified with postcolonialism and postmodernism. Ann-Marie MacDonald's Fall On Your Knees provocatively reworks the formal and thematic dimensions of magic realism by presenting a story of a mixed-race Cape Breton family from a lesbian feminist perspective, demonstrating that the Maritimes can be a viable setting for magic realist works. Through her magic realist treatment of characters, MacDonald begins to explore the race, gender and sexual politics that exist both within the Piper family and the community at large. Fall On Your Knees displays a heightened awareness of other literary texts and cultivates a consciously metafictional approach to the writing of fiction. The novel combines an exploration of the nature and limits of the knowable and a playful recreation of history with a realistic presentation of specific political concerns

Border Trickery and Dog Bones: A Conversation with Thomas King

Thomas King discusses whether or not he thinks Green Grass, Running Water is a Canadian novel, a Native novel, or both, the borders that cut between races, and the discomfort that the insider/outsider phenomenon creates for certain groups of readers. He also articulates his resistance to being labelled a comic writer and makes comparisons between Green Grass and Truth and Bright Water. He later discusses his radio show, Dead Dog Café, and his photography

Lamb Wave Propagation in Varying Thermal Environments

During flight, launch, and reentry, external surfaces on aerospace vehicles undergo extreme thermo-acoustic loads resulting in structural degradation. Structural health monitoring techniques are being devised to evaluate the health of these structures by locating and quantifying structural damage during and after flight. One such technique uses Lamb wave propagation to assess damage on the surface and through the thickness of thin materials. The objective of this study was to assess the sensitivity of piezo-generated Lamb wave propagation to isothermal and thermal gradient environments using both theoretical and experimental methods. Experimental isothermal tests were conducted over a temperature range of 0-225 deg F. The changes in temperature-dependent material properties were correlated to measurable differences in the response signal\u27s waveform and propagation speed. An analysis of the experimental signal response data demonstrated that elevated temperatures delay wave propagation, although the delays are minimal at the temperatures tested in this study. Both these results and experimental group velocity dispersion curves verified theoretical predictions. Subsequent experimental testing in thermal gradient environments, with peak temperatures ranging 114-280 deg F, also displayed an observable yet minimal delay in wave propagation. Finally, theoretical simulations at temperatures up to 600 deg F revealed significantly increased delays in wave propagation