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LIGO Scientists Go To Summer Camp
LIGO Honorees Look Back On Their Stellar Journeys

LIGO Scientists Go To Summer Camp

- Contributed by Peter Shawhan

In early June, 32 scientists from all across the United States and Europe packed up their laptops and headed to Caltech for "LDAS Camp," a 4.5-day workshop designed to share expertise and bring a wider range of people "up to speed" on the sophisticated software tools being developed to analyze data from the LIGO interferometers. LDAS is short for LIGO Data Analysis System and the workshop, organized by Sam Finn of Penn State University in conjunction with members of the LIGO Laboratory, covered two different LIGO computing environments:

-- First, the Data Monitoring Tool (DMT), which runs a variety of diagnostic programs in "real time" to extract and record information about running conditions, detector performance, and transient signals in environmental monitoring channels, and to provide rapid feedback for interferometer operators and scientists;

-- Second, the LIGO Data Analysis System, which provides parallel processing resources for the computationally-intense search algorithms needed to detect weak gravitational wave signals, as well as data "conditioning" services and a database system to store astrophysical event candidates, environmental "triggers" generated by the DMT, and other types of information.

Attendees at Camp. On the first day of camp, everyone crowded into the conference room on the 6th floor of the Millikan library building (home of the LIGO Laboratory's Data and Computing Group) for a day of overview lectures and demonstrations. John Zweizig (Caltech) began by describing the DMT hardware and software architecture, including the "foreground" (ROOT interactive session) and "background" (C++ program) paradigms within which data monitoring can be done. Peter Shawhan (Caltech) demonstrated how the "guild" graphical user interface is used to retrieve and display information from the LDAS database. Kent Blackburn (Caltech) gave an overview of LDAS and its internal distributed software components ("APIs") which work together to execute high-level commands submitted by users. Philip Charlton (Caltech) then dissected the arguments of a specific LDAS user command which does a complete (though highly simplified) search for gravitational-wave "inspiral" signals before submitting the command to the LDAS system, tracking its progress using log files on the LDAS web site, and retrieving the results from the LDAS database.

Camp Goers Receive Instruction. The remaining days of the camp session were devoted to two parallel hands-on workshops--one devoted to LDAS, the other to the DMT--to give attendees some actual experience developing analyses to make use of the software infrastructure. In each case, mornings were generally spent on in-depth tutorials, while time was available in the afternoon for people to work through examples and extend them at their own pace.

In the LDAS workshop, Sam Finn covered the LIGO/LSC Algorithm Library (LAL), which provides the core functions for any scientific analysis done within the LDAS computing environment, as well as "LALwrapper," which loads and executes the higher-level "driver" code for a specific analysis algorithm. Each attendee went through the process of downloading, building and installing his/her own copy of LAL and LALwrapper, along with a standalone version of the LDAS "wrapperAPI" to permit code development without requiring a fully functional LDAS system. The next day, John Whelan (University of Texas at Brownsville) described the LAL software specification and practical programming tips, and demonstrated how to construct a new LAL "package." In the afternoon, each attendee had time to try their hand at implementing a LAL package of their own. The following day, Sam Finn and Philip Charlton conducted a tutorial on designing and implementing a parallel analysis, using the Message Passing Interface (MPI), to run within LALwrapper and take advantage of the parallel processing resources provided by LDAS.

Meanwhile, in the DMT workshop, John Zweizig and Daniel Sigg (LIGO Hanford Observatory) introduced the basic data objects and signal processing functions provided by the DMT software library. They then described the "DMT monitor environment" which provides convenient real-time access to LIGO data as it is collected at the observatories. The DMT library can be accessed interactively from within ROOT (an object-oriented analysis and display environment developed at CERN), making it possible to prototype an algorithm interactively before implementing it as a standalone "monitor." John and Daniel also described how to produce various kinds of output: "triggers" to be sent to the LDAS database and/or to activate an alarm in the control room; "trend" data (typically minute-by-minute summary values); data objects to be transmitted to an interactive "DMT Viewer" upon demand; and dynamically-generated HTML pages. While there are a handful of existing DMT monitors in active use at the observatory sites, many more aspects of the LIGO interferometers and associated instrumentation will need to be characterized and tracked. To this end, Peter Saulson (Syracuse University) led a round-table discussion on the future use of the DMT, about which John remarked, "I believe that it focused everyone who attended on what the DMT is meant to do and the kinds of monitors, etc. that still need to be written."

The last day of the gathering was set aside for attendees to spend some more time implementing an idea of their own, whether a LAL package, a parallel search algorithm, or a DMT monitor. Like any good camp, LDAS Camp ended with a cookout, hosted by John Zweizig and his wife, Anne, before everyone packed up and headed home, taking along a greater understanding of LIGO data analysis software.


LIGO Honorees Look Back On Their Stellar Journeys

- Contributed by Linda Turner

Dorothy Lloyd, Larry Jones and Irene Baldon. How often have we found ourselves wondering where time has gone, reflecting on the journey that has brought us to where we are today? I'm sure four of our LIGO colleagues were pondering this when they were recently recognized by Caltech for their long-time service to the Institute and the JPL community. Honored for 30 years of service were Dorothy Lloyd and Larry Jones; Irene Baldon for 20 years; and, for 15 years, Stan Whitcomb. In addition to the official ceremony, held in early June, LIGO hosted an afternoon reception for the honorees, giving us all an opportunity to congratulate our LIGO friends on reaching these service milestones in their careers. Looking over their tenure at Caltech, the award-winners reminisced on the journey that brought them finally to LIGO. Perhaps you'll learn something new about these special LIGO members.

Larry Jones. Born and raised an Indiana Hoosier, Larry Jones graduated from Purdue and took his first job in 1963 at the Jet Propulsion Laboratory (JPL) as a mechanical engineer for the Advanced Liquid Propulsion System Project. For the next several years, Larry was involved in the spacecraft program, first with the Surveyor and then the Mariner spacecraft. Working as a mechanical engineer with the Surveyor team, he monitored the contractors' propulsion system development at Hughes Aircraft in El Segundo and Thiokol's Reaction Motors Division in New Jersey, and monitored pre-flight operations at Cape Kennedy. He performed data analysis while working with the Mariner team. Following this, Larry left JPL and worked eight years in private industry, returning to JPL in 1979 as a test engineer at JPL's Edwards Test Station. Recalling his career prior to joining LIGO, Larry's favorite job at JPL was the SAWE Project (Simulation of Area Weapons Effects) for the Army's program of improving the realism of field combat training. His task was to conduct the field tests of the ballistics of air launches (simulating artillery and mortar fire) and the performance of explosive projectile systems; this included the fun job of designing an air cannon to launch the plastic projectiles.

In 1988, Larry transferred to the Caltech campus and joined the LIGO Project, where he served as technical manager of the task for the design, fabrication, and installation of LIGO's 16 kilometers of beam tube. With successful completion of the beam tube at both the Hanford and Livingston Observatories, Larry brought his expertise to the Detector Group, providing mechanical engineering support for the 40-meter laboratory revisions.

Splitting his time now between retirement and LIGO, Larry has more time to indulge in his hobbies: shopping for antiques and researching his families' genealogies. Proud parents of two grown children, Mark and Kari, Larry and his wife, Sandy, refinished the kids' bedrooms into guest rooms with an antique theme. Both anticipate his full retirement depending on the stock market recovery.

Dorothy Lloyd. In 1971, Dorothy Lloyd began her career at Caltech as a clerk typist in the Kellogg Radiation Lab in Physics. After working as a secretary in Humanities, an administrative secretary in Chemistry, and a technical illustrator in Graphic Arts, "Dot" returned to Physics in 1991 as an Administrative Assistant with LIGO. Within LIGO, her responsibilities have continually evolved to meet the demands of an extremely vibrant project. She is intricately involved in serving as a liaison between the procurement and accounting functions for LIGO, ensuring that purchase orders, change orders and invoices accurately reflect LIGO's investments, commitments, contracts, and approvals.

As she reflected over her tenure at Caltech, Dot has enjoyed most working with the students--watching them grow and graduate--and seeing many return to Caltech in various capacities. She feels grateful that while working consistently on campus, her career has revolved around all phases of campus life--academics, service, and a government project--providing a great variety of career opportunities. Dot has raised three sons, and is now raising a grandson. In her rare moments of personal time, she enjoys crossword puzzles and quick getaways to San Diego and Morro Bay.

Irene Baldon. Irene Baldon began her career at Caltech in 1981, when she came to work for Humanities and Social Services. While in H&SS, she worked with several professors who were involved in extremely interesting and diverse work--such as one who was in politics, both at the California and national level, another researching mental health at the turn of the century, and a third who was an historian researching material to be used in the movie Reds. Irene later transferred to the Treasurer's Office, where she provided support to the Assistant Treasurer. She found this experience extremely enlightening as she was privy to the inner workings, interests and needs of the Caltech campus. Nearly seven years ago Irene joined LIGO as our Travel Coordinator. And did LIGO need such a person! Since arriving here, she has arranged an estimated 4500 trips, both within the United States and around the world, and she currently coordinates over 195 travelers, including guests, job applicants, SURF students, as well as LIGO personnel from Caltech, MIT, and the observatories in Hanford and Livingston.

It's no coincidence that Irene, too, loves to travel. Recently she had the opportunity to venture both to Hanford and Livingston and experience first hand the observatories to which she had arranged so many trips! Growing up, Irene traveled all over the country with her parents, and continued to do so with her husband and daughter. This past summer, Irene finally took one of several dream vacations to the East Coast to see Gettysburg, Pennsylvania, Williamsburg, Virgina, and finally Washington, D.C. Her final "dream" vacations will be to her ancestral homeland of Innsbruck, Austria, as well as that of her husband's--County Cork, Ireland.

In her spare time, Irene enjoys reading, knitting and crocheting. She is especially proud to be a grandmother of two grandchildren and six step-grandchildren.

Stan Whitcomb. Honored for 15 years of service, Stan Whitcomb is a Caltech original, beginning here as a student in 1969. He continued his education at the "Harvard of the mid-West," the University of Chicago, which happens to be one of the largest producers of LIGO scientists: Robbie Vogt, Jordan Camp, Tom Prince, Bill Kells, as examples. Stan's originality as a Caltech student carried over into LIGO, as he had two starts on the project, first in 1980, then again in 1991. Stan describes his tenure at Caltech as "every 11 years"--a steady progression of his association with the Institute from student (1969), to assistant professor (1980) and staff scientist (1991). Being involved with LIGO since its infancy in the early '80's, Stan has seen enormous changes over the years, both in the staff and science of LIGO.

Whenever Stan can manage to find snippets of free time (in between his constant traveling between the two sites), he enjoys kite flying, hiking, cooking, and mysteries. He has bragging rights to "the most wonderful wife in the western United States" and admits to loving "the most worthless dog in the entire universe." Stan is looking forward to a well-deserved "sabbatical" in Australia in the middle of 2002, once the initial detector is operational.

To all our honored colleagues--Dorothy, Larry, Irene, and Stan--we salute your longevity of service within the Caltech community, and especially within LIGO. We are indeed fortunate to have each of you as part of the LIGO family.