a BiRD Overview

BiRD: A Browsing Interface for RGS Data

Rosario González-Riestra and Pedro M. Rodríguez-Pascual

XMM-Newton Science Operations Centre, ESAC

Introduction

BiRD is a browsing and visualization tool for XMM-Newton RGS fluxed spectra. It allows the user to browse and examine the data before downloading them from the XSA for full analysis.

The BiRD interface makes possible to select spectra through a variety of parameters, such as (e.g.) date of observation, level of exposure or type of object.

It also provides some basic visualization utilities, both for the RGS spectra and spectral images, as well as for the EPIC-pn images taken in parallel.

What is RGS?
The Reflection Grating Spectrometer in one of the instruments on-board XMM-Newton. Its purpose is to obtain high spectral resolution (from 100 to 500, FWHM) X-ray spectroscopy in the range 5-38 Å.
Two of the three XMM-Newton X-ray telescopes are equipped with RGS instruments. After the first week of operations, an electronic component of one one of the RGS2 chips failed, affecting the wavelength range from 20.0 to 24.1 Å. A similar problem occurred in early September 2000 with one of the chips of RGS1 covering 10.6 to 13.8 Å. The total effective area is thus reduced by a factor of two in these wavelength bands.
A detailed description of the characteristics and performance of the RGS instruments can be found in the XMM-Newton Handbook.
The RGS Chapter in the XMM SAS (Science Analysis System) User's Guide provides useful information about RGS data products and their analysis.
What are fluxed spectra?
RGS fluxed spectra are computed dividing the extracted spectrum by the effective area calculated from its corresponding response matrix (see the description of the SAS task rgsfluxer).
This procedure neglects the redistribution of monochromatic response into the dispersion channels, and therefore these spectra should not be used for any detailed spectral analysis of the data (e.g. measurement of line widths).
Nevertheless, fluxed spectra are extremely useful for visualizing the data free from the peculiarities of the instrument. This is especially so because of the possibility of combining data from both cameras into a single spectrum, thus eliminating many of the gaps between functioning detectors.
Fluxed spectra are given in physical units (photons/cm²/s/Å vs. Å).

Some useful links

The Reflection Grating Spectrometer on board XMM-Newton, den Herder, J.W. et al, 2001, A&A 365, L7
A technical description of the Reflection Grating Spectrometer on board XMM-Newton
XMM-Newton Users Handbook
User's Guide to the XMM-Newton Science Analysis System

Processing Details

As of October 2011, 8840 ODFs have been downloaded from the XMM-Newton Science Archive (XSA) and processed with SAS.

Data were processed with the SAS metatask rgsproc.
rgsproc was run using the target coordinates given in the XMM-Newton proposal
First order spectra (without background subtraction) were generated using 100% of the spatial PSF. A model background spectrum (generated with the SAS task rgsbkgmodel) was used for the background correction
Response matrices were computed for each spectrum with rgsrmfgen
Finally, a fluxed spectrum was created for each observation combining all the available RGS1 and RGS2 first order spectra with rgsfluxer

Additional Information available in BiRD

In addition to the spectra themselves, the BiRD interface provides other information that might be useful for the interpretation of the data:

Start time of the observation
Target name as provided in the XMM-Newton proposal
Target coordinates as provided in the XMM-Newton proposal
RGS effective exposure time (taken as the average of the exposure time of the RGS1 and RGS2 spectra)
An estimation of the quality of the combined RGS1+RGS2 fluxed spectrum
Galactic Hydrogen column density, obtained from Dickey and Lockman (1990)
From the SIMBAD database:
- Name
- Coordinates
- Type of object
- Redshift (if applicable)
  SIMBAD was queried to derive a first target identification and classification using the target name given in the XMM-Newton proposal as input. In the cases where a SIMBAD object could not be unambiguously selected using the target name, the procedure was done manually, examining the different identifications of nearby objects. For a number of cases, the type of object was obtained from the abstract of the scientific justification of the proposal.
  Some particular cases:
  - Survey fields have been assigned the SIMBAD Type 'Region defined in the sky'
  - Solar System objects have been assigned Types 'Planet' or 'Comet', as applicable

Some Numbers...

Object Types

The BiRD database includes 3150 different objects. Twenty two of them have been observed more than twenty times:

Object SIMBAD Type N. of observations

M 31 LINER-type Active Galaxy Nucleus 82

Mkn 421 BL Lac - type object 57

EXO 0748-676 Low Mass X-ray Binary 52

LMC Galaxy 46

Crab Pulsar 39

Galactic Centre Region defined in the sky 38

N 132D SuperNova Remnant 37

Vela SuperNova Remnant 37

AB Dor Rotationally variable Star 34

M 33 Galaxy 31

SNR 0102-72.3 SuperNova Remnant 30

Object SIMBAD Type N. of observations

3C 273 Quasar 29

Coma Cluster Cluster of Galaxies 27

Chandra Deep Field-South Region defined in the sky 27

HR 1099 Variable of RS CVn type 27

CAL 83 X-ray Binary 23

Capella Variable of RS CVn type 23

HD 81809 Spectroscopic binary 23

Lockman Hole Region defined in the sky 22

AMS 16 Quasar 21

PKS 2155-304 BL Lac - type object 21

Her X-1 Low Mass X-ray Binary 21

These objects belong to 161 different types. SIMBAD types with more than twenty different objects are:

SIMBAD Type N. of objects N. of observations

Cluster of Galaxies 350 830

Seyfert 1 Galaxy 321 659

Quasar 207 331

Seyfert 2 Galaxy 198 299

Galaxy 188 343

SuperNova Remnant 102 362

X-ray source 102 142

Pulsar 94 304

Low Mass X-ray Binary 77 291

Radio Galaxy 77 104

Star 65 188

High Mass X-ray Binary 53 153

Cataclysmic Variable Star 49 63

High proper-motion Star 49 61

LINER-type Active Galaxy Nucleus 44 164

gamma-ray source 44 73

Cataclysmic Var. AM Her type 42 75

gamma-ray Burst 41 70

SIMBAD Type N. of objects N. of observations

Variable Star 40 91

Nova 40 74

T Tau-type Star 37 68

HII Galaxy 35 46

Interacting Galaxies 35 80

Group of Galaxies 34 51

Galaxy in Group of Galaxies 33 57

BL Lac - type object 31 145

Open (galactic) Cluster 30 49

Radio-source 30 51

Active Galaxy Nucleus 27 36

Region defined in the sky 27 523

Galaxy in Cluster of Galaxies 27 34

Wolf-Rayet Star 26 64

Dwarf Nova 23 31

White Dwarf 22 64

Emission-line Star 21 41

Exposure Times

The median exposure time of the RGS spectra is 20 ksec. Observations longer than 120 ksec (i.e. about one revolution long) are:

ObsId Object SIMBAD Type Texp (sec)

0147440101 IC 4329A Seyfert 1 Galaxy 135366

0204730301 GX 339-4 Low Mass X-ray Binary 134421

0606150101 PG 1126 -041 Seyfert 1 Galaxy 134006

0605540101 AWM 7 Cluster of Galaxies 133777

0504370401 BL Lac BL Lac - type object 133591

0147800201 2A 0335+096 Cluster of Galaxies 133509

0604960401 CDFS Region defined in the sky 133380

0202670801 SGR A* Radio-source 133274

0112210501 NGC 3783 Seyfert 1 Galaxy 132918

0555780201 CDFS Region defined in the sky 132871

0202670601 SGR A* Radio-source 132720

0204730201 GX 339-4 Low Mass X-ray Binary 132641

0306870101 Mrk 335 Seyfert 1 Galaxy 132577

0555780101 CDFS Region defined in the sky 132533

0300430101 NGC 3256 Interacting Galaxies 132422

0202670701 SGR A* Radio-source 132271

0600540601 Mkn 335 Seyfert 1 Galaxy 131768

0302900101 NGC 5408 Emission-line galaxy 131663

0305540701 rho Oph Star in Nebula 131257

0200370101 BP Tau T Tau-type Star 131020

0673580401 IRAS 13224-3809 Seyfert 1 Galaxy 130668

0655450101 SWIFT J2127.4+5654 Seyfert 1 Galaxy 130492

0202670501 SGR A* Radio-source 130234

0503490201 MACS J2243.3-0935 X-ray source 129737

0653380301 NGC 5408 Emission-line galaxy 129715

0605800401 Fairall 9 Seyfert 1 Galaxy 129638

0400620101 NGC 1399 Galaxy in Cluster of Galaxies 129507

0555630501 SN 1006 SuperNova Remnant 129034

0554680101 NGC 5044 Galaxy in Group of Galaxies 128468

0502290101 PSR J0030+0451 Pulsar 128374

0653380201 NGC 5408 Emission-line galaxy 128103

0650510601 M33 Galaxy 127737

0670950101 NGC 891 Galaxy in Group of Galaxies 127536

0670750101 PSR J0108-1431 Pulsar 127517

0555170301 PKS 0558-504 Seyfert 1 Galaxy 127502

0152840101 3C 120 Seyfert 1 Galaxy 127339

0654030101 CIZA J2242.8+5301 Cluster of Galaxies 127221

0109890501 A 665 Cluster of Galaxies 127165

0672780101 CID-42 n/a 126963

0653510401 1H 0707-495 Seyfert 1 Galaxy 126831

0501790101 NGC 2547 Cluster of Stars 126812

0504780501 HCG 62 Cluster of Galaxies 126695

0300270201 XX Cha T Tau-type Star 126637

0200080701 Jupiter Planet 126617

0651900201 WPVS 007 Seyfert 1 Galaxy 126525

0653860101 SN 1006 SuperNova Remnant 126446

0673580201 IRAS 13224-3809 Seyfert 1 Galaxy 126414

0673580301 IRAS 13224-3809 Seyfert 1 Galaxy 126309

0111800101 M 81 LINER-type Active Galaxy Nucle 126006

0555170501 PKS 0558-504 Seyfert 1 Galaxy 125817

0560180401 SGR 1627-41 gamma-ray Burst 125528

0655050101 NGC 55 Galaxy 125522

ObsId Object SIMBAD Type Texp (sec)

0555170401 PKS 0558-504 Seyfert 1 Galaxy 125515

0555781001 CDFS Region defined in the sky 125411

0653380501 NGC 5408 Emission-line galaxy 125382

0651610101 3C 279 Quasar 125376

0555782301 CDFS Region defined in the sky 125347

0605800301 NGC 7213 Seyfert 1 Galaxy 125329

0147800101 Sersic 159-03 Cluster of Galaxies 125283

0109141301 Mkn 766 Seyfert 1 Galaxy 124998

0555700101 Rabbit X-ray source 124940

0604960601 CDFS Region defined in the sky 124938

0600980101 X Per Double or multiple star 124925

0601930501 cl 2137+0027 Cluster of Galaxies 124803

0305780101 Perseus Cluster of Galaxies 124792

0652480201 MBM12 Molecular Cloud 124762

0155960501 1E 1207.4-5209 Pulsar 124577

0147511601 Lockman Hole Region defined in the sky 124439

0107460701 NGC 3516 Seyfert 1 Galaxy 124406

0653320101 PSR J1734-3333 Pulsar 124275

0101440801 SU Aurigae Variable Star of Orion Type 124158

0155960301 1E 1207.4-5209 Pulsar 123872

0604961801 CDFS Region defined in the sky 123767

0305540601 rho Oph Star in Nebula 123758

0406200101 Centaurus cluster Cluster of Galaxies 123656

0673580101 IRAS 13224-3809 Seyfert 1 Galaxy 123372

0555780301 CDFS Region defined in the sky 123368

0652210101 NGC 185 Seyfert 2 Galaxy 123252

0029740701 MCG--6-30-15 Seyfert 1 Galaxy 123174

0550950101 NGC 424 Seyfert 2 Galaxy 122827

0511580101 1H0707-495 Seyfert 1 Galaxy 122784

0301600101 V1647 Ori Variable Star of FU Ori type 122622

0502120101 NGC4261 LINER-type Active Galaxy Nucle 122484

0604960901 CDFS Region defined in the sky 122232

0504260101 Hydra A LINER-type Active Galaxy Nucle 122220

0029740801 MCG--6-30-15 Seyfert 1 Galaxy 122218

0552510101 NGC 1521 Galaxy 122126

0412990601 Vela SNR SuperNova Remnant 122036

0153750701 Vela SNR SuperNova Remnant 122015

0109880101 A 478 Cluster of Galaxies 122010

0604961001 CDFS Region defined in the sky 121776

0305370101 ESO 198-G24 Seyfert 1 Galaxy 121648

0550640101 MCG-02-14-009 Seyfert 1 Galaxy 121600

0606020101 CTB37B SuperNova Remnant 121537

0107460601 NGC 3516 Seyfert 1 Galaxy 121494

0651770101 XLSSJ022738.3-031758 Cluster of Galaxies 121250

0555170201 PKS 0558-504 Seyfert 1 Galaxy 121228

0653510601 1H 0707-495 Seyfert 1 Galaxy 120787

0604960301 CDFS Region defined in the sky 120784

0555780901 CDFS Region defined in the sky 120772

0153951401 PSR B0833-45 Pulsar 120716

0604960701 CDFS Region defined in the sky 120297

0604960101 CDFS Region defined in the sky 120210

0653380401 NGC 5408 Emission-line galaxy 120017

The Brightest Targets

The brightest objects observed with RGS (those having more than 25 cts/sec in the extracted RGS1 spectrum over the full wavelength range) are:

Obsid Object Type of Object cts/sec

0122330701 Crab Pulsar 233

0122330801 Crab Pulsar 232

0118700101 Crab a Pulsar 226

0410180301 RS Oph Symbiotic Star 177

0312790101 Crab Pulsar 174

0202401101 Cyg X-1 High Mass X-ray Bina 173

0137550801 Crab Pulsar 171

0202401201 Cyg X-1 High Mass X-ray Bina 154

0153750401 Crab Pulsar 99

0412592601 Crab Pulsar 93

0160961501 Crab Pulsar 90

0160961201 Crab Pulsar 88

0202760201 Cyg X-1 High Mass X-ray Bina 87

0160960201 Crab Pulsar 86

0160960301 Crab Pulsar 86

0093562701 GX 339-3 Low Mass X-ray Binar 83

Obsid Object Type of Object cts/sec

0111360201 GX 339-4 Low Mass X-ray Binar 79

0112921501 GRO J1655-40 Low Mass X-ray Binar 76

0112921401 GRO J1655-40 Low Mass X-ray Binar 75

0202760501 Cyg X-1 High Mass X-ray Bina 65

0202760401 Cyg X-1 High Mass X-ray Bina 64

0127720501 V4743 Sgr Nova 55

0202760301 Cyg X-1 High Mass X-ray Bina 55

0111360101 Cyg X-2 Low Mass X-ray Binar 50

0136140301 XTE J1650-500 Low Mass X-ray Binar 50

0303280101 Cyg X-2 Low Mass X-ray Binar 43

0656780601 MAXI J1659-152 Black Hole Candidate 39

0411082701 Mkn 421 BL Lac - type object 39

0561180501 Cyg X-2 Low Mass X-ray Binar 38

0610000401 Cyg X-1 High Mass X-ray Bina 31

0551340201 4U 1820-30 Low Mass X-ray Binar 29

0411080301 Mkn 421 BL Lac - type object 26

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