Follow-on Science Instrument

Contract NAS8-01129


Monthly Status Report Numbers 013 and 014

March & April 2003


HETG Themes:
X-GEF Preliminary Results
HRMA FWHM monitoring


Prepared in accordance with DR 972MA-002; DPD #972

Prepared for

National Aeronautics and Space Administration

Marshall Space Flight Center, Alabama 35812


Center for Space Research; Massachusetts Institute of Technology; Cambridge, MA 02139


1.0 Distribution List for Monthly Status Report



MIT-External Electronic:

FD03/Mike Smith, MSFC                   Carl.M.Smith@msfc.nasa.gov

PS41/Steve Morris, MSFC                 Steven.D.Morris@msfc.nasa.gov

SD50/Martin Weisskopf, MSFC            martin.weisskopf@msfc.nasa.gov


MIT-External Hardcopy:

                                    None specified.



            MIT-Internal Electronic:

                                                Elaine Tirrell                egt@mit.edu

                                                Gail Monahan              gmonahan@mit.edu


MIT-Internal Hardcopy:

                                                Claude Canizares         Room 3-234 (via Gail Monahan)

                                                Deepto Chakrabarty     Room 37-501 (via Elaine Tirrell)

                                                Kathryn Flanagan        Room NE80-6103 (via Elaine Tirrell)

                                                File                              (via Elaine Tirrell)



Please send distribution requests and other comments on this document to dd@mit.edu .


2.0 Schedule of Past and Future Events Relevant to HETG




Past Events


Mar. 23-26

HEAD meeting, Mt. Tremblant, Canada

M. Jimenez-Garate; A. Juett;

S.C. Gallagher; K.A. Flanagan


Chandra Quarterly


April 21-25

Star Formation Meeting, Madrid Spain

(N.S. Schulz)

April 30

XMM AO3 proposals due





Future Events


May 4-7

Constellation X Spectroscopy Workshop, Columbia Univ., NY


May 23

NERQUAM meeting, Cambridge MA

S. Gallagher

May 25-29

AAS 202nd Meeting, Nashville, TN


May 31 – June 4

The Riddle of Cooling Flows …

(M. Wise)

June 12-13

Chandra Users Committee meeting at CfA


June 17-20

Multiwavelength Cosmology , Mykonos Island, Greece.

T. Jeltema, C. Canizares

June 24-26

Chandra Peer Review


July 14-17

Short Course in EXAFS Data Collection and Analysis, Brookhaven National Lab

J. Lee

July 13-26

IAU, Sydney, Australia: Symp.218, "Young NSs …";

JD17: “… Atomic Data for X-Ray Astronomy”;

JD18: “Quasar Cores and Jets”; JD20 “Frontiers of High Res Spectro’py”

(J. Lee, DPH)

July 21-26

10th Marcel Grossmann Meeting, Rio de Janeiro

M. Jimenez-Garate; (N.S. Schulz)

July 26-30

AGN Physics with the SDSS, Princeton, NJ

S. Gallagher

July 31 –


International Cosmic Ray Conference, Tsukuba, Japan

(G. Allen)

Aug. ?

Chandra Quarterly Review


Aug. 3-8

SPIE meeting, San Diego

H. Marshall: HETG Flight Cal.; KAF;

Sept. 16-18

Four Years with Chandra, Huntsville AL


Sept (TBD)

SIRTF Cycle 1 proposals due


Oct. 13-19

5th Microquasar Workshop , Tsinghua, Beijing


Oct. 27-28

Chandra Calibration Workshop II, Cambridge MA


Oct. 28-31

Stellar-Mass, Intermediate-Mass, and Supermassive Black Holes , Kyoto, Japan


Nov. ?

Chandra: IAR and Quarterly Review


Nov. 17-22

Young Compact Binaries in the Galaxy and Beyond, La Paz, Mexico


Dec. 8-12

Multiwavelength AGN Surveys, Cozumel, Mexico




3.0 Instrument Status and Science Support



3.1 Flight Events and HETG Instrument Status


The HETG continues to function with no outstanding issues.

In March and April there were 6 HETG observations. Among them of note were one HETG GTO observation of TV Crt and two observations of bright point sources in TE mode useful for HRMA FWHM monitoring GX 339-4 and Cyg X-1 (see below.)


3.2 Science Support to CXC, SWG, etc.


The key ingredient in the HETG’s high spectral resolution is the high spatial resolution provided by the HRMA. We have an ongoing monitoring of the width of the HRMA’s PSF core to catch any drift in the HRMA width (expected due to defocus caused by optical bench length changes due to degassing.) The FWHM plot was updated recently with several observations and continues to show a remarkably constant FWHM value, see the Plot on the next page.



4.0 GTO Science Program

4.1 Observations and Data status

The final GTO target list for Cycle 5 was submitted and reconciled with other GTO and GO conflicts in preparation for the Peer Review in June. The three HETG GTO targets totaling 707 ks are listed in the table below – note that one of them will be competed in the Peer Review.


There was analysis progress on past GTO observations, briefly summarized here: NGC 5506 paper progress; TV Crt data received, analysis in progress; Orion Trapezium second paper resubmitted; N132D results organized and model grid added to ratio-ratio plot of regions; E0102 mass determinations and errors finalized.



Cycle 5


Science Theme


Obs ID

Seq. No.



Observer /


Start Date

Comments & Analysis

Talks and


4U 1957+11







M. Nowak


Will be competed in Peer Review









J. Lee




Orion Nebula Cluster

“Hot” Stars






N. Schulz





4.2 Science theme progress

The HETG GTO science efforts span a range of “science themes” given in the list below. Detailed progress in these areas will be picked up in future months’ reports.


GTO Science Theme


(for App’ix A)


(HETG in caps)

Date of last [next] reporting

Assembler of theme material

“Cool” Stars

Cool Star


September, 2002.

Dave Huenemoerder

“Hot” Stars

Hot Star


October, 2002.

Norbert Schulz

X-ray Binaries & Accretion Disks



man, jmm, psw

December, 2002.

Norbert Schulz, Mike Nowak

Supernova Remnants




May, 2002.

Dan Dewey

Isolated Neutron Stars


MDS,hlm, nss

January, 2003.

Mike Stage, Herman Marshall

Galaxies & Clusters of Galaxies

Gal., Clust.


August, 2002.

Michael Wise, Tesla Jeltema

Active Galactic Nuclei and Jets

AGN, Jet



June, 2002.

Herman Marshall

Inter-Stellar Medium



February, 2003.

Adrienne Juett, Norbert Schulz

Inter-Galactic Medium



July, 2002.

Taotao Fang


4.3 HETG-related Software: Development, Evaluation, and Support


(No update on s/w this reporting period.)



4.4 Presentations (March and April)


Kathryn A. Flanagan, “Estimating the Oxygen Ejecta Mass in E0102-72”, Poster at HEAD meeting, March 2003.

Kathryn A. Flanagan, “Chandra Observations of the Bright Eastern Knot of Puppis A”, Poster at HEAD meeting, March 2003.

Sarah C. Gallagher et al., “Testing Unification: Examining the X-ray Properties of Seyfert Host Galaxies”, Poster at HEAD meeting, March 2003.

Mario Jimenez-Garate, “Spectral Signatures of an Accretion Disk Corona during the Low State of Hercules X-1”, Talk at HEAD meeting, March 2003.

Adrienne M. Juett et al., “X-ray Absorption in the Interstellar Medium”, Poster at HEAD meeting, March 2003




4.5 Publications (March and April), see also: http://space.mit.edu/csr_pubs.html


“The Evolution of Cluster Substructure”, Tesla E. Jeltema, Claude R. Canizares, Mark W. Bautz, David A. Buote, in Carnegie Observatories Astrophysics Series, Vol. 3: Clusters of Galaxies: Probes of Cosmological Structure and Galaxy Evolution, ed. J. S. Mulchaey, A. Dressler, and A. Oemler (2003).

5.0 Systems and Engineering Support


5.1 Documentation and “Design Knowledge Capture” and 5.3 Anomalies, Insert/retract, etc. Support


No activities in these areas in March and April.


5.2 Spares Retest and Test Instrumentation


Test Instrumentation

A summary of lab test equipment used on the HETG project was given in the HETG Quarterly charts (4/1/03). A variety of grating-facet and HETG-level testing was carried out during the HETG design and construction phase and is summarized in the following list:


Visual inspection


Thermal cycling


Laser Reflection - period

X-ray Grating Evaluation Facility (X-GEF) - efficiency

Alignment to HESS

Vibration of HETG

Outgassing/particulates monitoring

S/C-as-installed video inspection


The disposition of this equipment will be decided and made clear by the end of this contract, Fall 2004.


Spares Retest

The X-ray efficiency data on the Vacuum Storage Gratings (VSG), collected most recently this past February, have been preliminarily analyzed. In all, 8 HEG gratings and 6 MEG gratings have been maintained in laboratory vacuum and now tested for up to 7 years since their fabrication in 1995-1996.

A detailed report on VSG data taken through 1998 (Version 2.0, http://space.mit.edu/HETG/vsg/vsg.html ) showed good period stabilitythrough the LR tests. The X-GEF tests showed some drift in X-ray diffraction efficiency especially for the MEG gratings. At that time contamination on the X-GEF SSD and PSPC detectors was identified, see Appendix of Version 2.0 report above.

In early 1999 the X-GEF SSD window was cleaned and the PSPC window replaced – removing the contamination. X-GEF tests were then carried out in mid-1999 as well as near the end of 2000 and just recently in February 2003.

The plot at right is an updated version of Figure vsg.4 of the 1998 report and shows the stability of the VSG gratings’ measured efficiencies over the past 4 years (during which time there was no further contamination buildup in the X-GEF system.) The efficiencies are plotted relative to their initial post-fabrication measured values (the central dashed line level) with the dotted lines at +/-10% change from the initial values. The connected diamonds show the trend for a given grating. Five different efficiencies are plotted: MEGs at 1 and 4 keV and HEGs at 1, 4, and 8 keV.

The stability seen here indicates there is no extreme evolution of the gratings’ diffraction properties with time and a similar result for the flight HETG is to be expected.



6.0 Management


6.1 Program Office & NASA Support


Responded to MSFC inquiries about HETG test equipment and its future disposition in relation to the CXC follow-on contract.


6.2 MIT-internal management activities


HETG postdoc hiring: offer made to and accepted by Andy Young, currently at U Maryland.



7.0 Open Issues, Problems, etc.


There are no open issues or problems regarding the HETG.