Blog from July, 2008

Science Tools Working Group

No meeting again this week. There's not a lot of news to report.

Since July 26 current release version of the Science Tools is v9r7. Here are the differences from v9r6p3. Most of the updates relate to facilitating porting the tools to the hmake build environment that will be used at GSSC, which also entails making the code buildable on a wider variety of systems. Eric W. determined the needed changes and posted them as JIRA issues for the respective package owners. These should be transparent to users of the Science Tools. Toby and Marshal have extensively updated the skymaps and pointlike packages; from the release notes I get the impression that the functionality has not changed.

Data products: No news.

Databases and related utilities

No news

Likelihood analysis

No news

GRB tools

No news

Pulsar tools

Masa reminds us of an issue that I think Jim originally pointed out regarding barycenter arrival time corrections; gtbary changes every time-related quantity in the files that it processes. As a result, likelihood analyses of phase-selected photons can give noticeably-incorrect results because the event times no longer correspond to the correct part of the pointing history file. Masa originally proposed eliminating gtbary, since the pulsar tools can generate and apply barycenter arrival time corrections on the fly. However, enough users depend on barycenter arrival time corrections that eliminating gtbary does not look useful. I think that Masa is working on a way that gtbary can indicate in a FITS file whether the times have been corrected

Observation simulation

Max R. has updated the PulsarSpectrum package in response to a couple of needed tweks

User interface and infrastructure (& utilities)

No news

Source Catalog

Met last week and will meet tomorrow. Issues in source associations (with members of other catalogs) were discussed last week

Science Tools Working Group

No meeting again this week. There's not a lot of news to report this week.

The current release version of the Science Tools is v9r6p3. Here are the differences from v9r5p6. It has a few updates that will be of interest to interactive users of the Science Tools (as opposed to ASP).

Data products: No news.

Databases and related utilities

No news

Likelihood analysis

Jim updated gtltcube to optionally apply a zenith angle cut in calculating the livetime cubes. The cut cannot be applied later. Cuts on zenith angle can significantly influence the exposure for pointed observations (when the FOV can become partially occulted by the earth). Note: Likelihood does not handle zenith angle cuts in data, however, meaning that for pointed-mode analyses, ROIs and source regions need to be defined carefully, or time range filtering should be applied to select time ranges when a particular region is not at large zenith angle.

See the note below about gtselect

GRB tools

No news

Pulsar tools

From Masa: "Nothing special in the pulsar tools development. FYI, James and I are doing final checks before tagging the pulsar tools with improved time-handling classes, etc., although users will see only a few differences on the surface with the new versions."

Observation simulation

Toby's relaxing of the consistency checking in astro, which allows the simulated pointing histories from the GSSC to be used with gtobssim and Gleam, is in the current release of the Science Tools. This doesn't solve the problem of why the consistency checks were failing, but allows simulations, e.g., of L&EO observations, to proceed.

User interface and infrastructure (& utilities)

Jim has fixed a bug in gtselect to have it update the TSTART and TSTOP keywords if multiple input FT1 files are given. This is important because gtmktime uses these keywords.

It appears that with the current release of Science Tools we are now using Ape instead of PIL for prompting. I'm not sure how you would notice the difference but it seems to not have broken anything

Source Catalog

Met twice last week. Jean presented and we discussed First-Light source detection and counterpart assessments.

Science Tools Working Group

We last met on May 21; once again this week we will not meet. There's not a lot of news to report this week; also I discovered late that my e-mail polling for development news did not get sent; at least I'm not sure where it went. So in some cases below 'No news' means 'None that I know of'.

The current release version of the Science Tools remains v9r5p6. Most of the development since (as measured by LATEST builds) has been Toby's work on the pointlike package; see note on the pointfind application below.

Data products: No news.

Databases and related utilities

No news

Likelihood analysis

No news

GRB tools

No news

Pulsar tools

No news

Observation simulation

No news

User interface and infrastructure (& utilities)

No news. An upcoming topic will be when to move to the Event Class Handling system that Jim has proposed and developed.

Source Catalog

Met last week. Toby presented an update on pointfind - the high-TS spurious source problem has been solved but the tradeoff currently is in numbers of good detections. Ludovic presented results on source detection in the new obssim3 data set. Jean presented the Catalog Group's interests in issues regarding First Light products.