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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

14822 results found.

  1. XRF040701: VLA Observations
  2. GRB 030324: Detection and Color of Host Galaxy
  3. GRB040511: Redshift identifcation
  4. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  5. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  6. INTEGRAL detection of activity from SGR1806-20
  7. GRB 040223 : Optical observation (non-detection)
  8. GRB040106, likely optical afterglow
  9. GRB031203: K' Photometry of the likely GRB host
  10. GRB 031203: Radio detection
  11. GRB 031203: IR NTTobservations do not confirm REM detection
  12. IPN detection of activity from SGR1806-20
  13. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  14. IPN detection of continued activity from SGR1806-20
  15. XRF 030723: Subaru Optical Observations
  16. XRF 030723: Detection of the likely host galaxy
  17. GRB 030913, optical candidate
  18. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  19. IBAS detection of bursts from SGR 1806-20
  20. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  21. IPN detection of continued activity from SGR1806-20
  22. XRF 030723: Detection of a rebrightening in the optical afterglow
  23. XRF030723: Re-analysis of ROTSE-III early images
  24. GRB 030725: optical observations.
  25. GRB030725, optical transient observations
  26. XRF030723 Radio Observations
  27. GRB030725, possible optical transient
  28. XRF030723: Palomar observations and proposed counterpart
  29. XRF 030723, optical observations
  30. Konus-Wind detection of the bursts from SGR1806-20 region
  31. IPN detection of renewed activity from SGR1806-20
  32. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  33. HETE detection of burst from SGR1806-20
  34. GRB 021206, Radio afterglow candidate
  35. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  36. GRB030501 localized by INTEGRAL
  37. GRB030329 observed as a sudden ionospheric disturbance (SID)
  38. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  39. OT GRB 030329: early spectrum
  40. GRB 030329 VLBA Observations
  41. GRB 030329: Sub-millimeter detection
  42. GRB 030329: Radio observations at GMRT
  43. GRB030329a: detection by Konus-Wind
  44. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  45. GRB 030329, optical spectroscopy
  46. GRB 030329: visual observations
  47. RXTE detection of GRB 030329 afterglow
  48. Possible GRB030323 localized by INTEGRAL
  49. GRB030323: Detection on 2003/03/24
  50. VLT/FORS2 spectra of GRB 030323
  51. GRB030323, ROTSE-III detection of possible optical counterpart
  52. Possible GRB 030320 localized by INTEGRAL
  53. GRB030226: Analysis of Chandra data
  54. Chandra detection of the X-ray afterglow of GRB 030226
  55. GRB 030228, optical observations
  56. GRB030227 localized by INTEGRAL
  57. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  58. GRB 030217: Optical Observations at 4, 5, and 6 Days
  59. GRB030115, WSRT radio observations - correction to GCN 1864
  60. GRB 030131: marginal optical detection
  61. GRB030115, WSRT radio observations
  62. A long GRB detected by INTEGRAL
  63. GRB 030115: Radio detection of IR candidate
  64. GRB 030115: IR observations with IRSF/SIRIUS
  65. GRB030115: R-band counterpart of IR candidate
  66. GRB030115: TAROT optical observations
  67. GRB 030115, optical candidate
  68. GRB 021112: Evidence for Another Dark Optical Afterglow
  69. GRB021219: a long GRB localized by INTEGRAL
  70. IPN detection of continued activity from SGR1806-20
  71. GRB 021211, optical observations
  72. GRB021211: Measurement of Early Time Afterglow
  73. IPN detection of renewed activity from SGR1806-20
  74. IPN detection of continued SGR1900+14 activity
  75. GRB021125 : A long GRB localized by INTEGRAL
  76. IPN detection of possible reactivation of SGR1900+14
  77. GRB 021113: Evidence for a Dark Optical Afterglow
  78. Detection of activity from SGR 1900+14 with the RXTE/PCA
  79. GRB 020813; likely host galaxy.
  80. GRB 021008, optical observations
  81. GRB 021004: optical spectroscopy on Oct 11
  82. GRB021004: optical observation
  83. GRB 021004: WC wind?
  84. GRB 021004: Optical observations, AUDE network
  85. GRB 021004: optical spectroscopy
  86. IRAM Millimeter detection of GRB 021004
  87. GRB 021004 radio search
  88. XRF 020903: optical observation at Kyoto
  89. GRB020322 : HST/STIS observations
  90. IPN detection of a burst from SGR1900+14
  91. XRF 020903, optical observations
  92. Confirming no variability for GRB02081
  93. GRB020813: Early Time Magnitude
  94. GRB 020813, radio detection
  95. GRB020812: optical observations
  96. GRB 020813 multiband optical observations
  97. HST Imaging of the Host of GRB 011121
  98. GRB 020410: Discovery of Probable OT by HST
  99. GRB 020625, optical observations
  100. GRB/XRF 020427, detection of an underlying system with the VLT

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