Gemini e-Newscast #54

by xzhangIn this release:
Puzzling Accretion onto a Black Hole in M101
Data Reduction Forum Is Now Open
A Successful TEXES Run in 2013
Large and Long Programs at Gemini Announced
Soliciting Feedback on Solaris SPARC Usage
Early December Propagation of the Gemini South Laser

Puzzling Accretion onto a Black Hole in M101

Gemini observations support an unexpected discovery in the galaxy M101. The target, M101 ULX-1 is an ultraluminous X-ray source—ultraluminous in the sense of excessive accretion-powered X-ray emission for a stellar-mass black hole. Jifeng Liu (National Astronomical Observatories of China) and collaborators measured the black hole’s mass, finding that it is 20–30 times the mass of the Sun. Thus, this is not an example of an intermediate mass black hole (as many researchers in the field expected), which would have a mass roughly 100–1000 MSun. Such objects remain elusive, leaving an observational gap between stellar-mass and supermassive black holes. A further unexpected result is that the X-ray emission is relatively soft, dominated by low-energy X-ray emission, which tends to be characteristic of much more massive black holes, not lower-mass cases like M101 ULX-1. A Gemini press release is posted, and the complete results are published in Nature.


Artist’s visualization of the environment around M101 ULX-1, showing a stellar-mass black hole (foreground) with accretion disk. Gas from the companion Wolf-Rayet star (background) feeds the black hole’s voracious appetite. Gemini Illustration by Lynette Cook.


Data Reduction Forum Is Now Open

We are pleased to announce the release of the Gemini Data Reduction User Forum, located at http://drforum.gemini.edu/. This is intended as a user-supported site for the trading of ideas, scripts, best practices, and for taking part in user-driven public discussions on data reduction processes and strategies. If you have written a script, procedure, tip, or a description of your own process that you think other Gemini users may find helpful in reducing their data sets, please consider posting it here. The Forum's "start here" page gives a brief introduction and some points to note when posting or taking part in discussions. Both the observatory and the Users’ Committee for Gemini are keen to see this Forum well utilized and helpful to a broad segment of our user community. To encourage your involvement, Gemini Director Markus Kissler-Patig has agreed to award Director’s Discretionary observing time to two individuals who will be selected based on the usefulness of their posts. More details will be provided at the forum site soon.


A Successful TEXES Run in 2013

The high-resolution mid-infrared spectrograph TEXES completed an eleven-night visitor-instrument run at Gemini North on November 23. The TEXES team of John Lacy (University of Texas at Austin) and Matt Richter (University of California, Davis), encountered poor weather that kept the telescope closed part of the time, but they still managed to complete about 80% of the Band 1 observations and 60% of the Band 2 observations. The scientific programs included an investigation of the atmosphere above Io’s volcanoes, chemistry studies of protoplanetary disks around young stars, and determination of the evolutionary state of a massive star deeply embedded in its natal cloud. If community interest remains high, and the instrument team continues to be able to support observations, we expect to have another TEXES visit to Gemini in 2014.


Large and Long Programs at Gemini Announced

The Announcement of Opportunity for Large and Long Programs at Gemini has been released. The first deadline is for Letters of Intent, which are due February 3, 2014. The complete proposals are due March 31, 2014, for observations to begin in semester 2014B. See the announcement for complete requirements and eligibility, which differ from those of regular semester proposals.


Soliciting Feedback on Solaris SPARC Usage

Use of the Solaris operating system in astronomy has decreased significantly in the last 10 years. Therefore, Gemini is considering no longer distributing Solaris binaries for public tools such as the Phase I Tool and Observing Tool (PIT and OT). This will simplify software development and focus on the more widely used systems. We are soliciting feedback from users about the potential impacts of this change. If you or your institution still use Solaris machines and require Solaris (SPARC) versions of the PIT and OT, then please inform Bryan Miller via email (bmiller@gemini.edu) by January 13, 2014. Solaris distributions will continue to be offered for 2014B proposals, and any change will be announced at least four months in advance.


Early December Propagation of the Gemini South Laser

This image showing the propagation of the Gemini South laser guide star system is dedicated to the memory of Vincent Fesquet. Vincent worked tirelessly to make the Gemini South laser guide star system work efficiently and reliably. Leave your memories of Vincent at: www.gemini.edu/staff/vfesquet

Special thanks to the W.M. Keck Observatory and Pete Tucker for the extra assistance necessary to make this laser propagation possible in early December 2013.

Image by Manuel Paredes, Gemini Observatory/AURA