HETG

Follow-on Science Instrument

Contract NAS8-01129

 

Monthly Status Report No. 003

May 2002

 

HETG Science Theme: Supernova Remnants

 

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

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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

ES84/Martin Weisskopf, MSFC            martin@smoker.msfc.nasa.gov

 

MIT-External Hardcopy:

                                    None specified.

 

 

            MIT-Internal Electronic:

                                                Deborah Gage             dgage@space.mit.edu

                                                Gail Monahan              gmonahan@mit.edu

 

MIT-Internal Hardcopy:

                                                Claude Canizares         Room 37-582G (via Gail Monahan)

 

 

 

 

 

 

 

 

 

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

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2.0 Schedule of Past and Future Events Relevant to HETG

 

 

Date	Past Events	Comment
May 24- June 3	4th Microquasar Workshop, Corsica, France.	Dr. Lee attending.

 

 

 

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3.0 Instrument Status and Science Support

 

 

3.1 Flight Events and HETG Instrument Status

 

The HETG continues to function with no outstanding issues.

 

There were 4 targets observed in 5 observation intervals by the HETG in May 2002. None of these are in the HETG GTO program, however for the Her X-1 TOO observation HETG post-doc Mario Jiminez-Garate is the Investigator.

 

The Capella observation made in late April has been preliminarily analyzed and the HETG resolution, wavelength scale and “ACIS chip gaps” appear fine in the CXC pipeline-produced data products.

 

3.2 Science Support to CXC, SWG, etc.

 

Worked with CXC/Ishibashi to diagnose “spokes” seen in mono-energetic HEG MARX simulation and to update the HEG sector files to remove the artificial spokes.

 

Provided input for CXC’s “Educational Use of Chandra” survey, see 4.6 below.        

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4.0 GTO Science Program

4.1 Observations and Data status

Progress in the GTO program observations and data analyses are noted in the Table of Appendix A.

 

4.2 Science theme progress

The HETG GTO science efforts span a range of “science themes” given in the list below. This month progress and plans in the Supernova Remnants theme are presented.

 

GTO Science Theme	Date of last reporting
Stars	Not yet reported
X-ray Binaries and Accretion Disks	Not yet reported
Supernova Remnants	May, 2002.
Neutron Stars	Not yet reported
Galaxies and Galaxy Clusters	Not yet reported
Active Galactic Nuclei	Not yet reported
ISM and IGM Absorption	Not yet reported

 

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Supernova Remnants Progress

Introduction

The study of supenova remnants provides information on i) the end point of a star's evolution, ii) the creation and dispersal of heavy elements (beyond H and He) in the universe, and iii) the events that produce a neutron star or black hole, and on iv) the acceleration of cosmic rays. These remnants generally have a hot plasma component which emits x-rays corresponding to the elements present, in particular the HETG can measure lines from O, Ne, Mg, Si, S, and Fe.

In addition, some SNRs exhibit "non-thermal" X-ray emission due to synchrotron or non-thermal bremsstrahlung radiation mechanisms. Separating these lines for measurement requires the spectral resolution of the HETGS. Because the sources are extended and not simple point sources the HETG resolution attainable depends on the details of the size and spatial structure of the source. Much of our research effort is involved in teasing high-resolution results from the SNR observations.

HETGS observations have been carried out as part of our GTO program on four supernova remnants: "E0102" in the SMC, "N132D" and "N103B" both in the LMC, and "Cas A" in our Galaxy. Information on the specific observations is given in the Appendix A table. For each remnant "true color" images of the SNR are shown at left (from http://hea-www.harvard.edu/ChandraSNR/ ) and the dispersed image on the ACIS-S array is shown to the right. We take each remnant in turn and summarize our analysis status and scientific results.

 

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E0102            

This SNR was observed very early in Chandra's first year and its well defined ring structure shows up beautifully in the dispersed image above. Bright lines of O, Ne, and Mg dominate the spectrum with little of the "Iron forest" of lines appearing here. This clean, well characterized spectrum is used to advantage in calibrating the ACIS detector.

 

There is a wealth of data to be extracted from the E0102 observations some of which has been presented at various conferences since the data were obtained. At the moment we are just putting the finishing touches (elemental mass estimates) on a comprehensive paper (Flanagan et al. 2002) covering several analyses of the data - some key results are shown in the following figures taken from the paper.

The plot at left shows for the measured Oxygen line fluxes contour lines describing regions of allowed shock model parameters, temperature and ionization age (tau).

In the figure at right the location measured as the distance from E0102 center of an elements' H- and He-like ion emission shows a clear correlation with the ionization age, tau, at which that element has greatest emission. With the "younger" material on the inside this suggests the motion of a "reverse shock" through the medium from outer to inner radii.

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This image of E0102 is the result of our prototype spatial-spectral analysis software and shows a model of the Ne X line emission on the sky which is color coded for regions of high velocity: red regions are moving away at 500 to 2200 km/s and the green regions are moving toward us at ~500 to 1300 km/s; a few regions, colored blue, are moving toward us at velocities in the 1400 to 2200 km/s range. The structure of velocity seen here is suggestive of an expanding cylinder or partially filled spherical shell seen a little off axis hinting at the 3-D spatial-velocity structure of the remnant.

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N132D               

This remnant is larger and spatially more complex than E0102. There are many bright "filamanents" in the remnant - long, curvy but generally narrow regions. As the true color image of this remnant shows, there is quite a variation in this remnant from location to location. Using in-house "filament analysis" software it is possible to measure the intensity of O and Fe emission lines in each of over a dozen filament features in N132D.

 

 

 

 

 

This plot shows a point for each identified N132D feature depending on the ratio of O VIII to O VII and the ratio of Fe-17A to O VIII for that region. The scatter in the plot further displays the variation in plasma conditions through out the remnant.

 

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N103B           

The smallest of our remnants in terms of size on the sky is N103B. Because of this smaller size it is possible to obtain a reasonable spectrum of N103B by essentially analyzing it with standard grating analysis techniques.

 

Most of the "usual suspects" show up in this N103B spectrum, however, the clear presence of Oxygen in this spectrum (at 19A, 22A), not clearly seen in previous CCD spectra, puts into question previous conclusions that this was a type Ia supernova. Most notable in comparison to E0102 and N132D are the very bright lines of Si which contain useful counts in both HEG and MEG spectra. We have fit these data with a multi-temperature plane-parallel shock model and are working to get a measure of overall elemental abundances. A preliminary spatial-spectral analysis of the Si lines was carried out and may be able to produce accurate maps of the Si resonance and forbidden line emission.

 

 

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Cas A            

This remnant fills about one half of the S3 chip of ACIS and represents about the most extended source one could imagine observing with the HETG. Fortunately it is very bright and so there are significant numbers of counts from individual small bright knots and filaments. As in the case of N103B the remnant is very bright in the Si line and the HEG and MEG spectra contain useful information.

 

Our analysis to date has focused on one bright Si-rich narrow feature. Analyzing the dispersed images of this feature shows the Si lines to be clearly blue-shifted by a doppler velocity of order 2000 km/s.

 

The location of Si lines expected are labeled at the top of the figure, Si XIV, Si XIII. The measured locations are consistently shifted to the left due to a Doppler velocity of order 2000 km/s. This result is in agreement with previous Einstein/FPCS and recent XMM/EPIC-MOS observations (Markert et al. 1983, ApJ, 268, 13; Willingale et al. 2001, A&A 381, 1039) but is much more specific in its spatial region and accuracy of Doppler shift and maybe a useful calibrator for the XMM data sets.

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Supernova Remnants Plans

 

There is much more that can be done with these data and we are also looking to get additional data as part of the GTO program (another observation of E0102 at a different roll angle to complement our initial data set is in the peer review competition for Cycle 4.) Some of these additional efforts are described here:

 

E0102

- finish estimate of abundances in E0102.

- measure line fluxes and ratios in localized regions, e.g., the SE arc.

- compare fluxes with power-law shock model values.

- repeat the Ne X spatial-velocity analysis including obsid 968 as well.

- investigate 3-D models for their agreement with the Ne X spatial-velocity results and the variation of

ionization stage with position.

- create s/w to jointly analyze the Cycle 1 and Cycle 4 E0102 observations.

N132D

- try including an Fe "pseudo continuum" to better measure Ne and Mg line fluxes in the various regions.

- plot a model grid of line ratios over the O7/O8 vs Fe/O8 scatter plot.

- establish limits on non-thermal X-ray emission using radio observations.

N103B

- present more detailed results at COSPAR meeting in October.

- further spatial-spectral analysis.

- establish limits on non-thermal X-ray emission using radio observations.

Cas A

- for the Si feature combine grating line flux values with ACIS zeroth-order continuum values

to get n_H/n_Si and feature masses.

- analyze additional features in Si and S for flux, temp, mass, and doppler velocities.

General

- write a paper on the analysis techniques used for these extended sources, a "spatial-spectral SNR paper".

- work with ISIS s/w team to determine useful spatial spectral s/w functions to be added to ISIS.

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

 

A variety of software has been created or modified in-house for use in analyzing supernova remnant observations. These include:

·      3-D Shell emission geometry code used with MARX, "shell.c".

·      Line ratio table creation (w/ISIS) and contour plotting (in IDL).

·      "Filament analysis" s/w written in IDL.

·      "Spatial-spectral" s/w written in IDL.

J. Lee worked with Tim Kallman to add new atomic physics info into the XSTAR program and test it on Chandra data.

 

4.4 Presentations (May)

 

Lee, J., “The Chandra HETGS & RXTE observation of the microquasar GRS 1915+105: A hot disk atmosphere and cold gas enriched in Fe and Si”, given at 4^th Microquasar Workshop, May 27 – June 1, 2002.

 

 

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

 

Ogle, P.M., et al., “Testing the Seyfert Unification Theory: Chandra HETGS observations of NGC 1068”, ApJ submitted, 2002.

 

Lee, J.C., et al., “The shape of the relativistic Fe line in MCG--6-30-15 measured with the Chandra HETGS and RXTE'”, 2002, ApJ, 570, L47 [CSR-02-15, revised info]

 

Lee, J.C. co-author on Fabian A.C., et al., “A long hard look at MCG--6-30-15 with XMM-Newton”, MNRAS, in press (astro-ph/0206095), 2002.

 

Chakrabarty D., Wang Z., Juett A.M., Lee J.C., Roche P., “The X-Ray Position and Infrared Counterpart of the Eclipsing X-Ray Pulsar OAO 16 57-415”, 2002, ApJL, 573, in press (astro-ph/0203124)

4.6 Student and Postdoc Involvement, Sept. 1999 – May 2002

The following information was requested from HETG PI Claude Canizares by the CXC and is listed here for reference. This information was entered into the CXC web system as requested at

http://cxc.harvard.edu/udocs/surveys/educ/frontpage.html

 

Theses:

Year   Name,   Type,      Title :

2001 Amalia Hicks   M.S.              “Chandra X-Ray Spectroscopy and Imaging of the Galaxy Cluster PKS 0745-191”

2001 Taotao Fang    Ph.D.            “X-ray Absorption by the Intergalactic Medium”

 

5.0 Systems and Engineering Support

 

5.1 Documentation and “Design Knowledge Capture”

 

No activity this period.

 

5.2 Spares Retest and Test Instrumentation

 

1. Vacuum Storage Gratings are due for re-test. The test is delayed because of failure of the Vacuum Gauge Controller. The controller was returned to the manufacturer for repair. Expected return to MIT in early June.

 

2. The four computers which are part of the X-GEF and LR test instruments will no longer be supported long before the end of the planned Chandra mission. We have begun a low level effort to identify spares as other computers in CSR are replaced with more powerful versions. We anticipate minimal hardware costs.

 

3. The primary archival machine, named "caliber", operates on the Sun OS4 operating system, which is no longer supported. We are still operating on Sun OS4 because the software is configuration controlled. We have to perform additional manual steps to manage data storage because the volume of data accumulated is a challenge for OS4. We anticipate operating another computer on Solaris in parallel, so that when "caliber" fails, we will have confidence in the replacement hardware and software.

 

4. The Labview software for the MAC's was written by a now defunct outside vendor. We are working on upgrading the documentation.

 

5.3 Anomalies, Insert/retract, etc. Support

 

No actions this month.

 

 

6.0 Management

6.1 Program Office & NASA Support

 

Letter dated May 30, 2002 sent to MSFC to make additional changes to the contract’s GFE list – we do not anticipate any further equipment list changes in the near term.

 

6.2 MIT-internal management activities

 

Started paper work to order two new computers for use by grad student and post doc.

 

7.0 Open Issues, Problems, etc.

 

 

There are no known critical open issues or problems regarding the HETG.

 

There is an outstanding request for Prof. Canizares’ trip to give an invited talk at the “Making Light of Gravity Conference” in Cambridge, UK – letter dated 5/13, amount to be approved: $2,988.40.

 

There is an outstanding request to MSFC for approval to purchase a pair of computers for HETG use, letter dated 5/30, amount of purchase is $7,406.00

 

Appendix A. GTO Observation Status Tables

 

Notes:

1. Entries indicating progress during this period are shown in this font.
2. For CSR Publication references (CSR-YY-NN) see http://space.mit.edu/csr_pubs.html
3. Up-to-date observation information can be obtained from http://cxc.harvard.edu/cda/ using the WebChaSeR link.

 

Cycle 4 (to be finalized after Peer Review in June)

Object	AO	Obs ID	Seq. No.	Expos. (ks)	Observer / Analyst	Start Date	Comments & Analysis	Talks and Publications
4U 1626-67	4	---	---	[100.0]	N. Schulz		Prop. No.: 04400027
Sco X-1	4	---	---	[15.0]	N. Schulz		Prop. No.: 04400046
H1426+428	4	---	---	[102.0]	T. Fang		Prop. No.: 04700987
Mrk 290	4	---	---	[250.0]	J. Lee		Prop. No.: 04700988
TV Crit	4	---	---	[100.0]	D. Huenemoerder		Prop. No.: 04200007, Competitive w/GOs
E0102	4	---	---	[140.0]	K. Flanagan		Prop. No.: 04500008, Competitive w/GOs

 

Cycle 3

Object	AO	Obs ID	Seq. No.	Expos. (ks)	Observer / Analyst	Start Date	Comments & Analysis	Talks and Publications
MRC 2251-178	3	2977	700416	[150.0]	J. Lee/ H. Marshall	---	Scheduled: 9/10/02
NGC 7469	3	3147	700586	[70.0]	J. Lee/ H. Marshall	---	Scheduled: 9/4/02
1H 0414+009	3	2969	700408	[93.0]	T. Fang	---	Scheduled: 8/1/02
GX 349+2	3	3354	900193	35.2	N. Schulz, A. Juett	4/9/02	For ISM study; Observed on 4/9; data available 5/2 [4/02]
NGC 2362	3	2525, 2526	200133, 200134	44.5, 43.8	N. Schulz, P. Wojdowski, J. Kastner/RIT	3/28/02, 4/23/02	Previewed the data. Observed 4/23 [4/02]
1ES 1028+511	3	2970, 3472	700409	21.8, 69.6	T. Fang	3/27/02, 3/28/02	Both data sets are in-house [4/02]
3C 279	3	2971	700410	108.2	T. Fang, H. Marshall	3/21/02	Data reduced; jet seen in zo image. Data are in-house [3/02].
IRAS 18325-5926	3	3148, 3452	700587	56.9, 51.1	J. Lee	3/19/02, 3/23/02	Data are in-house [3/02].

 

Cycle 2

Object	AO	Obs ID	Seq. No.	Expos. (ks)	Observer / Analyst	Start Date	Comments & Analysis	Talks and Publications
Cyg X-2	2	1016	400094	15.1	N. Schulz, A. Juett	8/12/01	ISM study: cold absorption edges
Cas A	2	1046	500112	69.9	K. Flanagan, D.Dewey	5/25/01	Si knot analysis started [3/02].	In CRC Royal society talk 2002.
4U 0142+61	2	1018	400096	25.4	N. Schulz, A. Juett	5/23/01	Finishing additional analysis [3/02]	ApJ, 2002, 568, pp. L31, HEAD-2002[4/02] CSR-02-16[3/02]
Mrk 766	2	1597	700213	90.5	P. Ogle, J. Lee	5/7/01	Paper in preparation [4/02]
NGC 4696	2	1560	600117	85.8	M. Wise	4/18/01
EXO 0748-676	2	1017	400095	49.0	N. Schulz, H. Marshall, M. Jimenez-Garate	4/14/01	Analyzed burst spectra; Created spectral lightcurves	HEAD02
SS 433	2 2 1	1019, 1020, 106	400097, 400098, 400019	23.7, 23.0, 28.9	H. Marshall, N. Schulz	3/16/01, 11/28/00, 9/23/99		CSR-02-01, CSR-01-78
H 1821+643	2	1599	700215	101.3	P. Ogle, T. Fang	2/9/01		CSR-02-16.5[4/02], CSR-01-69
Iota Orionis	2	599, 2420	200075	37.6, 12.9	N. Schulz, P. Wojdowski	2/7/01, 2/8/01	Data reviewed
TY Pyx (HD77137)	2	601	200076	49.8	D. Huenemoerder	1/3/01		(none)
N103B	2	1045, 2410, 2416	500111	74.0, 25.7, 17.6	K. Flanagan, J. Migliazzo, D. Dewey	1/1/01, 1/3/01, 1/2/01	NEI, vshock, and Si 2-D analyses.[4/02] 1-D and 2-D analyses started [3/02]	Poster: HEAD-2002[4/02]
NGC 5506	2	1598	700214	90.0	P. Ogle, J. Lee	12/31/00		Paper in preparation[4/02]
ZW 3146	2	1651	800119	167.8	M. Wise	12/25/00	Re-analysis started	Cluster paper in draft

 

 

Cycle 1

Object	AO	Obs ID	Seq. No.	Expos. (ks)	Observer / Analyst	Start Date	Comments & Analysis	Talks and Publications
NGC 1068	1	332	700004	46.3	H. Marshall, P. Ogle, J. Lee	12/4/00	Examine z-o pileup	Paper in submitted.
4U 1626-67	1	104	400017	40.0	N. Schulz	9/16/00		CSR-01-81
AR Lac	1	6,7,8, 9,10,11	20000N: 4,5,6,7,8,9	32.5,7.5, 7.5,32.6, 7.3,7.3	D. Huenemoerder	9/11/00- 9/19/00		Internal draft circulated.[4/02] Paper started [3/02], CSR-01-112
Abell 1835	1	49896 511	800019	9.8 127.0	M. Wise	8/25/00 8/26/00	Re-analysis started	Cluster paper in draft
N132D	1	121, 1828	500008	22.3 77.6	K. Flanagan, D. Dewey	7/19/00 7/20/00	Fe and O line ratios from many regions/features	CSR-01-10,26, Y2Chandra01
TW Hydra	1	5	200003	48.3	D. Huenemoerder, J. Kastner	7/18/00		CSR-02-02, CSR-01-29
NGC 4486	1	241	600001	38.5	M. Wise	7/17/00
GX 301-2	1	103	400016	40.0	N. Schulz	6/19/00	Re-analysis initiated [3/02]	Draft paper begun [3/02], AAS00
NGC 1399	1	49898, 240, 2389	600214 600000	13.2 44.1 14.8	M. Wise	5/8/01 6/15/00 5/8/01
Vela X-1	1	102	400015	28.4	N. Schulz	4/13/00		ApJ, 2002, 564, L21
MCG –6-30-15 (w/Fabian)	1	433	700105	128.2	H. Marshall, J. Lee	4/5/00		Lee et al 2002, CSR-02-15 [3/02], CSR-01-02
NGC 4151	1	335	700007	48.0	H. Marshall, P. Ogle	3/5/00		CSR-00-87
PSR B0656+14	1	130	500017	38.1	H. Marshall	11/28/99	LETG/HRC	Paper accepted, CSR-02-12[3/02]
PKS 2149-306	1	336, 1481	700008	36.0 54.8	H. Marshall	11/18/99 11/20/99		CSR-01-67
Trapezium	1	3, 4	200001 200002	50.1 31.3	N. Schulz, D. Huenemoerder	10/31/99 11/24/99	Detailed modeling work continued	CSR-01-118, CSR-00-89, CSR-00-75
4U 1636-53	1	105	400018	29.8	N. Schulz	10/20/99		AAS00
PKS 2155-304	1	337, 1703, 1705	700009 700261 700263	39.1 26.2 25.8	H. Marshall	10/20/99 5/31/00 5/31/00	HETG and LETG w/ACIS-S	Paper accepted.[4/02] Responded to referee [3/02]
Cyg X-1	1	107, 1511	400020	2.5 12.6	N. Schulz, H. Marshall, J. Miller	10/19/99 1/12/00	Second paper reviewed. Paper in process [3/02]	ApJ, 2002, 564, pp. 941 (CSR-01-57), HEAD00
II Peg (HD 224085)	1	1451	200010	43.3	D. Huenemoerder	10/17/99		CSR-01-50
Q0836+7104	1	1450, 1802	700006	61.0 14.1	H. Marshall	10/17/99 8/25/00		CSR-01-67
PKS 0745-191	1	510, 1509, 1509	800018	45.3, 40.4, 39.9	M. Wise	10/14/99 4/25/00 3/4/00	Re-analysis started	ApJ submitted, Hicks et al. [3/02]
PSR B0833-45	1	131	500018	36.1	H. Marshall	10/12/99		HEAD00
NGC 1275	1	333, 428	700005 700201	53.2 25.0	H. Marshall	10/10/99 8/25/00	Determined PL spectral slope	None of note
E0102	1	120, 968	500007	88.2, 49.0	K. Flanagan, J. Houck, A. Fredricks, D.Dewey	9/28/99 10/8/99	Fluxes and ratios in “arc”. Initial calc O mass.[4/02]	More progress on ApJ paper [3,4,5/02], CSR-01-10,11,24,25,26, Y2Chandra01
Object	AO	Obs ID	Seq. No.	Expos. (ks)	Observer / Analyst	Start Date	Comments & Analysis	Talks and Publications

Cycle 1, end.