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RXTE News Archive: 2004 RXTE


Recommended RXTE Cycle 10 Targets Released!

December 3, 2004

The Stage 1 review for RXTE Cycle 10 took place in November, 2004. Scientists from all over the world convened to discuss the 150 unique proposals that were submitted for consideration this year. The proposals and targets that were recommended to NASA Headquarters by the review panel are now available online. NOTE: Cycle 10 proposal numbers are distinguished by their leading two digits: 91NNN.

PIs should receive email notification of the results of their proposal, along with comments from the review panel, within the next several weeks. Congratulations to all successful Cycle 10 PIs!

Cycle 10 Deadline Past---Proposals are In!

September 28, 2004

The deadline for Cycle 10 proposal submission was Monday, September 20, 2004. We received 150 proposals in response to the call for proposals as part of ROSS-04. A total of over 61 Mega- seconds observing time was requested, for an oversubscription factor of about 5.1. We are now preparing for the Stage 1 review, to be held in mid-November. PIs should be notified by mid-December and the list of recommended targets will be made available through the RXTE GOF Web site. We thank the X-ray community for your continued interest in RXTE!

RXTE & XMM Squeeze Neuton Star Equation of State

September 8, 2004

Dr. Tod Strohmeyer (NASA GSFC) and Adam Villarreal (graduate student, University of Arizona) used RXTE and XMM/Newton to obtain the best measurements yet of the mass and radius of a neutron star. Announcing their findings at the September High Energy Astrophysics Division (HEAD) meeting in New Orleans, Villarreal said, "Our results are really starting to put the squeeze on the neutron star equation of state." Read more at:

Goddard Space Flight Center Press Release: Scientists Gain Glimpse of Bizarre Matter in Neutron Star
(includes computer animation)

RXTE Cycle 10 Proposal Due Date Extended to September 20, 2004;GO Funding May Increase!

July 27, 2004


NASA Headquarters has recently released an amendment to ROSS-04 concerning the RXTE Guest Investigator Program. The due date for proposals to the Rossi X-ray Timing Explorer RXTE Guest Investigator Program Cycle 10 described in Appendix A.8 is changed from Friday, September 10, 2004, to Monday, September 20, 2004. With this new deadline in place, there is now no conflict between the dates of the upcoming AAS HEAD meeting in New Orleans and the RXTE proposal deadline.You may see full text of the amendment to ROSS-04 .

Information regarding RXTE Cycle 10 proposal preparation and submission may be found on the RXTE Website.

Note that the Panel Report of the 2004 Senior Review of Astronomy and Physics MO&DA Programs recommended that RXTE's GO funding be enhanced. We expect that the amount of funding available to GOs will thus be increased somewhat in Cycle 10, though the exact amount is not known at this time.

As always, please send any questions to:xtehelp.

Michiel van der Klis wins NWO Spinoza prize!

June 24, 2004

Professor Michiel van der Klis, Professor of Astronomy at the Universiteit van Amsterdam Institute 'Anton Pannekoek', received the NWO Spinoza prize 2004 for his pioneering research into X-ray radiation from binary stars. In 1985 he clarified why X-ray radiation emitted by binary does not consist of stable pulses but instead of quasi-periodic oscillations. And in the 1990s his group hit the world headlines when they discovered the first X-ray star which rotated at 400 times per second around its axis. The existence of such a star had been predicted 16 years previously, but had not yet been proved." The NWO-Spinoza prize, which some regard as the 'Dutch Nobel Prize', is awarded by the Netherlands Organization for Scientific Research (NWO) to Dutch scientists who are at the very top of the research profession. The laureates are internationally renowned and are an inspiration to young scientists. Read some of Michiel's work:

RXTE Cycle 10: Shaping the Next Decade of XTE Science

June 14, 2004

Materials are now available to support PI's who wish to submit observing proposals for RXTE Cycle 10--- a component of NASA Headquarters' Research Opportunities in Space Science 2004 (ROSS-04). See our Proposals & Tools Page for all necessary instructions and steps for submitting a proposal. Notices of Intent are due on July 9, 2004. RXTE Cycle 10 proposal deadline is September 10, 2004. Cycle 10 observations commence around March 1, 2005 and will continue for 12 months. As was the case the last two years, this will be a two-stage review. Successful science PIs at US institutions will be invited to submit budget proposals at a date after the November 2004 science review. We encourage all interested scientists to propose your ideas for RXTE Cycle 10. As always, should you have questions during proposals preparation, contact the RXTE GOF for support. Good luck with your proposals!

New Email Addresses to Contact the RXTE Science Operations Facility (SOF)

May 4, 2004

The RXTE SOF email server has recently changed. RXTE users should update their addresses for communicating with the RXTE SOF to use the new address. In all cases, "xgo2.nascom.nasa.gov" or "xtesof.nascom.nasa.gov" should be replaced by "athena.gsfc.nasa.gov".

The affected addresses are xteplan, xtesof, and xtetoo. Please update your address book as follows (examples):


We apologize for any inconvenience this may cause our users.

Corrected Faint Background Models now Available

April 13, 2004

New faint models are being released that correct an oversubtraction of background rates late in all Epochs, and eliminate small trends. One model is mission-long, the others contain the same data, but separated out into individual gain Epochs. The details of the faint model are the same in both representations; the mission-long model is made available to simplify the analysis tasks for users. See the PCA Digest page for links to the models, and details of the correction.

RXTE Paper of the Month!

March 2004 Paper of the Month:

McHardy, et al, study the power spectrum of NGC 4051 across more than 6.5 decades in frequency by combining many years of RXTE monitoring with a short, high time resolution XMM observation. They find the timing characteristics of NGC 4051 to be similar to Cyg X-1 in its high state, as opposed to broad line AGN such as NGC 5506, which resembles Cyg X-1 in the low state. Their results suggest that there is not a single relationship between black hole mass and Power-Spectral break frequency, but may depend on at least one other parameter, such as accretion rate, black hole spin, or possibly both. As RXTE monitors more AGN, other systems can be analyzed in this fashion, and the relationship may become more clear.

For more RXTE-related publications, see the:

RXTE "Paper of the Month" Archive
Archive of all RXTE Publications (RXTE Results page)

RXTE Sees Superburst Effect Accretion Disk in Real Time

March 18, 2004

RXTE observations of a superburst halfway across the galaxy have provided scientists with their first-ever look at the moment-to-moment changes the burst inflicted on the nearby accretion disk. David Ballantyne (CITA at University of Toronto) and Tod Strohmayer (NASA/GSFC) report their findings in the Feb. 20 issue of the Astrophysical Journal Letters. The superburst acted like a "spotlight", illuminating the inner-most region of the accretion disk, and allowing RXTE to capture spectra of the disk every few seconds. According to Ballantyne, "This is the first time we have been able to watch the inner regions of an accretion disk, in this case literally a few miles from the neutron star's surface, change its structure in real time."

For more information:

Goddard Space Flight Center Top Story (includes computer animation)
NASA Headquarters Press Release
Astrophysical Journal Letters article ("The Evolution of the Accretion Disk around 4U 1820-30 during a Superburst")

New! RXTE-related Astronomical Notices

March 17, 2004

Now, the latest RXTE-related Astronomer's Telegrams, IAU Circulars, and GCN notices are only one click away: look for the blue "Astronomical Notices" button near the bottom of the RXTE GOF homepage. Clicking on it will take you to our "Latest RXTE-related Astronomical Notices" page, where you'll find RXTE-related ATELs, IAUCs, and GCN notices from the last 6 months. From there, you can also follow links to our archive of all RXTE-related notices, or the full archive of all RXTE Publications (also known as the "RXTE Results" page). Check them out!

Latest RXTE-related Astronomical Notices
RXTE Results page (archive of all RXTE-related publications)

RXTE Catches Morphing Magnetar

January 28, 2004

Alaa Ibrahim and coworkers discovered the first transient magnetar, XTE J1810-197, serendipitously during an observation of another magnetar nearby. Magnetars, a rare class of extremely magnetic neutron stars, are thought to be born with ultrahigh magnetic fields. The transient nature of this magnetar supports the theory that these objects may at first be too dim to see, but eventually brighten as the spinning star slows down and releases energy. Studying the history of XTE J1810-197 has involved several high energy observatories. Chandra was used to accurately pinpoint the location of the new object. Archival XTE data revealed that XTE J1810-197 brightened by a factor of about 100 around January 2003. Finally, the archives of the earlier international missions ROSAT and ASCA were mined, revealing the source as a dim, isolated neutron star as early as 1990. This exciting new development in neutron star evolution was presented at the Winter 2004 AAS Meeting in Atlanta, Georgia.

See this story on the Goddard Homepage.

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This page is maintained by the RXTE GOF and was last modified on Friday, 18-May-2007 15:39:38 EDT.