The Neil Gehrels Swift Observatory

Swift/BAT Hard X-ray Transient Monitor

Please Read Before Using These Results:README

The paper describing the Swift/BAT transient monitor is now available in the Astrophysical Journal: Krimm et al., 2013, ApJSS 209,14
Please reference this paper on all publications which make use of results from the BAT transient monitor.
HAK 31-Oct-2013

BAT went into an spontaneous reboot on Sept 10, 2019.
The complete science operation for BAT was restored on Sept. 20, 2019.
Therefore, no data are available for the BAT transient monitor from Sept. 10 to Sept. 20.

-- Amy Lien, Sept. 20, 2019


Old issues that have been resolved:

1. the number of enable detectors stop updating (starting from March 27, 2019).
This should only have small (likely negligible) effect on flux measurements.
This problem is fixed on Sept. 12, 2019.

2. a temporary loss of data communication on March 29 and March 30, 2019,
which causes the BAT transient monitor to produce data with zeros
during that time and later stop processing.
The loss of data communication has been resolved and we will
reprocess data in early April to fill the gap.
Please ignore those zeros from March 29 and 30.

-- Amy Lien, Apr 15, 2019 (with updates on Sept. 20, 2019)


Update on the anomalously low points in the light curves:
We have determined that the anomalously low points in the orbit and daily light curves
shown in several bright sources (e.g., Swift J0243.6+6124, MAXI J1820+070, and Crab)
are due to a software issue known as the "data overflow problem".
This problem occurs when the collected counts exceed the maximum value
that can be stored in the scaled map. As a result, the counts saturated
with the extra counts being wrapped around and stored as extremely low values.
We have reprocessed the full data set from 2012 to 2018
to remove these anomalously low points due to the overflow problem.
(We are still investigating the possibility to reprocess data on and before 2011,
since these data have slightly different format that require additional modification of current codes.
For light curves before 2011, we recommend using the BAT survey catalog: https://swift.gsfc.nasa.gov/results/bs105mon/).
-- Amy Lien, Apr 15, 2019


Update on the anomalously low points in the light curves:
We have determined that the anomalously low points in the orbit and daily light curves
shown in several bright sources (e.g., Swift J0243.6+6124, MAXI J1820+070, and Crab)
are due to a software issue known as the "data overflow problem".
This problem occurs when the collected counts exceed the maximum value
that can be stored in the scaled map. As a result, the counts saturated
with the extra counts being wrapped around and stored as extremely low values.
We have reprocessed the full data set from 2012 to 2018
to remove these anomalously low points due to the overflow problem.
(We are still investigating the possibility to reprocess data on and before 2011,
since these data have slightly different format that require additional modification of current codes.
For light curves before 2011, we recommend using the BAT survey catalog: https://swift.gsfc.nasa.gov/results/bs105mon/).
-- Amy Lien, Apr 15, 2019


The time-offset issue has been fixed.
-- Amy Lien, Feb. 10, 2017

The daily light curves now have three new columns showing the rates and significances for the current day, the previous day and the average of the last ten days.
-- Hans Krimm, Mar. 7, 2012
There is now a new page which includes the sources which are currently bright in the BAT transient monitor (see link below to Currently Detected Sources
-- Hans Krimm, Mar. 8, 2012l

On each individual source page you will now find a link to the source page in Simbad.

For the sources also found in the BAT Hard X-ray Survey there are now links to the survey light curves and spectra
-- Hans Krimm, Dec. 14, 2010

The daily light curves now have three new columns showing the acculumated exposure in the daily averages
-- Hans Krimm, Jan. 5, 2011

All detected sources on one page: Detected Sources (Public)
Flare stars light curves: Flare Stars (Subset of full list below) (Public)
MOJAVE radio sources light curves: MOJAVE (Subset of full list below) (Public)
Provisional (not yet verified) sources: Provisional Sources

Potentially interesting known sources: Interesting Known Sources
Unknown sources from transient_monitor: Transient Monitor Unknown Sources
Unknown sources from mosaic: Mosaic Unknown Sources Calibration Pointings: Blank sky locations (Public)

Red text indicates that the source has been detected in the BAT transient monitor.
Sources are considered detected under the following circumstances:

  • The mean rate is at least 3 mCrab (1 mCrab = 0.000220 ct/cm2/sec).
  • -OR- The peak rate for the source is at least 30 mCrab with at least a 7-sigma significance.
  • Data current through 23:17 UT, September 26 (DOY 269), 2023

    This page was last modified on Wed Sep 27 18:45:18 UTC 2023 (19.4578 hours later)

    Swift/BAT Transient Sources

    Source Name RA J2000 Degs Dec J2000 Degs Alternate Name Source Type Today# Yesterday# Tenday# Mean* Peak* Days* Last Day*
    1IGR J00234+61415.7400061.6850V1033 CasCV 0 0 5 1 ( 0)
    22CG 121+048.0000066.80001CG 121+03Gamma-ray source 0 0 1 1 ( 0)
    3V826 Cas8.7614661.3173Variable star 0 0 1 1 ( 0)
    4NGC 25311.9000-25.2830Sy----
    5RX J0052.1-731913.0921-73.31812E 0050.4-733HMXB 0 0 4 1 ( 0)
    6NGC 45418.5955-55.3988SWIFT J0114.4-5522Sy2----
    7QSO B0121-59020.9417-58.8066Fairall 9Sy1 1 0 4 1 ( 0)
    8NGC 52620.9758-35.0653Sy1.5 3 0 5 1 ( 0)
    9NGC 61223.4904-36.4930Radio galaxy 1 0 2 1 ( 0)
    10IGR J01363+661024.075066.1750[KRL2007b] 14HMXB 0 0 4 1 ( 0)
    11ESO 297- 1824.6549-40.0113Sy2 2 0 1 1 ( 0)
    12NGC 78830.2769-6.81586Sy2 2 31 353784 ( 6397)
    13QSO J0209+522632.393052.4430Leda 138501Sy1 2 0 3 1 ( 0)
    14NGC 86333.6400-0.766750Mrk 590Sy1.2----
    15NGC 93137.060831.3109Sy1.5 2 0 6 1 ( 0)
    16NGC 98538.6574-8.78761Sy1 1 40 253784 ( 6397)
    17ESO 416- 238.8058-29.6047Sy1.9 0 0 1 1 ( 0)
    18ESO 198- 2439.5817-52.1928Sy1 0 0 1 1 ( 0)
    19QSO B0241+6241.240462.468587GB 024100.7+621529Sy1 3 56 1253785 ( 6396)
    20SN 2006dd50.6740-37.2040SN 0 0 3 1 ( 0)
    21NGC 136553.4013-36.1408Sy1.8 2 81 853786 ( 6395)
    22ESO 548- 8155.5159-21.2440SWIFT J0342.0-2115Sy1----
    231H 0419-57766.5033-57.20066dFGS gJ042600.7-571202Sy1 1 0 3 1 ( 0)
    24NRAO 19070.6500-0.283000QSO B0440-003Quasar----
    25SWIFT J0444.1+281371.037528.21672MASX J04440903+2813003Sy2----
    26MCG-01-13-02572.9229-3.80944Sy1.2----
    27XSS J05054-234876.3500-23.8000Swift J0505.8-2351Sy2 HII 1 75 553785 ( 6396)
    284U 0517+1777.689616.4986IRAS 050708+1626Sy1.5 3 0 6 1 ( 0)
    29SWIFT J0513.4-654778.3680-65.7880NULLHMXB/NS 0 0 4 1 ( 0)
    30QSO B0513-00279.0478-0.150167Ark 120Sy1 2 0 1 1 ( 0)
    31ESO 362- 1879.8983-32.6583Swift J0501.9-3239Sy1.5 2 0 2 1 ( 0)
    32SN 1987A83.8750-69.2670SN 0 0 2 1 ( 0)
    33MCG +8-11-1188.723046.4390UGC 3374Sy1.5 5 35 2154269 ( 5912)
    34IGR J06074+220591.850022.08302MASS J06072661+2205477HMXB 0 0 3 1 ( 0)
    35Mrk 393.901371.0375Sy2 5 0 13 1 ( 0)
    36ESO 490- 26100.049-25.8939SWIFT J0640.4-2554Sy1.2----
    37Mrk 6103.05174.4269IC 450Sy1.5 1 44 858105 ( 2076)
    382CG 235-01112.500-20.4000Gamma-ray source----
    39Mrk 79115.63749.8093Sy1.2----
    40IGR J08023-6954120.570-69.9100DENIS-P J080241.6-695338X-ray source----
    41UGC 4730135.49460.1514Mrk 18Sy2----
    42MCG-01-24-012140.193-8.05608SWIFT J0920.8-0805Sy2 1 0 3 1 ( 0)
    43MCG+04-22-042140.92922.9092Sy1.2 1 0 2 1 ( 0)
    44Mrk 110141.30452.2863Sy1 2 0 1 1 ( 0)
    452CG 054+01141.35019.6330SN 1230SN 0 0 1 1 ( 0)
    46SN 1993J148.85069.0170SN 0 0 1 1 ( 0)
    47NGC 3227155.87819.8649Sy1.5 4 0 7 1 ( 0)
    48IGR J10252-6829156.252-68.4570[KRL2007b] 88X-ray source 0 0 1 1 ( 0)
    49NGC 3281157.967-34.8537Sy2 3 0 3 1 ( 0)
    50SWIFT J1038.8-4942159.688-49.78191RXS J103845.2-494709Sy1 0 0 2 1 ( 0)
    51IGR J10404-4625160.093-46.4240Swift J1040.7-4619Sy2----
    52Mrk 417162.37922.9644SWIFT J1049.4+2258Sy2 1 0 1 1 ( 0)
    53NGC 3516166.69872.5690Sy1.5 3 0 9 1 ( 0)
    54IGR J11085-5100167.210-51.0420[KRL2007b] 94X-ray source----
    55SWIFT J1112.2-8238167.949-82.6460NULLNULL----
    56IGR J11305-6256172.779-62.9470Swift J1131.0-6256HMXB----
    57IGR J11321-5311173.025-53.1830[KRL2007b] 98X-ray source 0 0 1 1 ( 0)
    58SWIFT J1200.8+0650180.2416.80642CGCG 041-020Sy2 0 0 3 1 ( 0)
    59IGR J12026-5349180.698-53.8350LEDA 38038Sy2 2 0 3 1 ( 0)
    60NGC 4051180.79044.5313Sy1.5 2 0 6 1 ( 0)
    61NGC 4074181.12420.3162ARK 347Sy2----
    62NGC 4102181.59652.7109Liner----
    63NGC 4138182.37443.6850Sy1.9 0 0 2 1 ( 0)
    64Virgo Cluster186.63012.7200Galaxy cluster 0 0 3 1 ( 0)
    65XSS J12270-4859186.995-48.89561RXS J122758.8-485343CV?----
    66GRS 1227+025187.4752.13300X-ray source 0 0 2 1 ( 0)
    67NGC 4593189.914-5.34425Sy1 2 0 4 1 ( 0)
    68IGR J12415-5750190.357-57.8340Swift J1241.6-5748Sy2 1 0 3 1 ( 0)
    693C 277.3194.95327.9810Coma ClusterGalaxy cluster 2 0 1 1 ( 0)
    70MCG+09-21-096195.99853.7917SWIFT J1303.8+5345Sy1----
    71NGC 4945196.363-49.4680Sy2 7 0 23 1 ( 0)
    72IGR J13109-5552197.680-55.8700PMN J1310-5552Sy1----
    73MCG-03-34-064200.602-16.7286Sy1.8----
    74SAX J1324.5-6313201.113-63.2230SAX1324.5-6313X-ray source 0 0 2 1 ( 0)
    75MCG -6-30-15203.974-34.2950ESO 383-35Sy1.2----
    76NGC 5252204.5674.54236Sy1.9 2 0 2 1 ( 0)
    771A 1343-60206.900-60.61804U 1344-60Sy1.5----
    78Mrk 279208.26469.3080MRK 279Sy1.5 0 0 1 1 ( 0)
    79Mrk 463209.01218.3710MRK 463Sy1Sy2/Merger 0 34 453788 ( 6393)
    80IGR J14175-4641214.265-46.69502MASS J14170366-4641411Sy2 0 0 1 1 ( 0)
    81ESO 511-G030214.843-26.6450Sy1 1 0 2 1 ( 0)
    82Mrk 813216.85419.8310Sy1 0 0 2 1 ( 0)
    83NGC 5728220.600-17.2531Sy2 3 0 3 1 ( 0)
    84IGR J14471-6319221.884-63.27902MASS J14471488-6317192Sy2----
    85IGR J14493-5534222.290-55.60002MFGC 12018AGN 0 0 2 1 ( 0)
    86IGR J14552-5133223.810-51.55002MASX J14551742-5134150Sy1----
    87IGR J15094-6649227.358-66.82302MASS J15092601-6649232CV/DQ Her----
    88Mrk 290233.96857.9026QSO B1534+580Sy1----
    89IGR J15360-5750234.000-57.8170IGR15360-5750X-ray source----
    90IGR J15479-4529237.060-45.4790NY LupCV/DQ Her----
    91IGR J16167-4957244.155-49.98001RXS J161637.2-495847CV----
    922CG 333+01244.250-49.30001CG 333+00Gamma-ray source----
    93IGR J16185-5928244.652-59.4550WKK 6471Sy1 NL----
    94IGR J16207-5129245.193-51.5020CXOU J162046.2-513006HMXB/SFXT 2 78 159795 ( 386)
    95Mrk 1498247.01751.7753SWIFT J1628.1+5145Sy1.9 1 0 1 1 ( 0)
    96IGR J16316-4028247.900-40.4670IGR16316-4028X-ray source----
    97CIZA J1638.2-6420249.567-64.3472Triangulum clusterCluster of galaxies 1 0 3 1 ( 0)
    98IGR J16558-5203254.023-52.06101RXS J165605.6-520345Sy1.2 0 0 1 1 ( 0)
    99AX J1700.2-4220255.105-42.31702MASS J17002524-4219003HMXB 1 0 1 1 ( 0)
    100H 1658-298255.525-29.9500V2134 OphLMXB 0 0 1 1 ( 0)
    1014U 1708-23257.100-22.8000Oph X-2X-ray source----
    102Oph cluster258.103-23.3500Galaxy cluster 6 0 7 1 ( 0)
    103NGC 6300259.248-62.8210Sy2 3 0 4 1 ( 0)
    1044U 1715-321259.698-32.17801H 1715-321LMXB 0 0 2 1 ( 0)
    105IGR J17195-4100259.898-41.01501RXS J171935.6-410054CV----
    106IGR J17200-3116260.025-31.28402MASS J17200591-3116596HMXB 2 0 4 1 ( 0)
    107IGR J17285-2922262.171-29.3820[KRL2007b] 241XRB 0 0 3 1 ( 0)
    108SWIFT J1729.9-3437262.537-34.6120NULLXRB/NS 0 31 755397 ( 4784)
    109IGR J17331-2406263.304-24.1430[KRL2007b] 247BHC----
    110SWIFT J1741.5-6548265.350-65.7910NULLXRB/NS----
    111XTE J1743-363265.750-36.3447[KRL2007b] 264SRC/X-ray 0 0 2 1 ( 0)
    112IGR J17460-3047266.580-30.7910IGR17460-3047X-ray source 0 0 1 1 ( 0)
    113IGR J17488-3253267.230-32.91402MASS J17485512-3254521Sy1 1 0 3 1 ( 0)
    1141RXS J175113.3-201214267.806-20.2040X-ray source 0 0 1 1 ( 0)
    115IGR J18027-1455270.697-14.9150Sy1 1 0 3 1 ( 0)
    116IGR J18135-1751273.363-17.8490HESS J1813-178SNR/PWN 1 0 1 1 ( 0)
    117IGR J18159-3353273.989-33.8900NULLX-ray source----
    118SAX J1818.7+1424274.68314.4030SAX1818.7+1424X-ray source 0 0 4 1 ( 0)
    119IGR J18325-0756278.125-7.93300CXOU J183228.3-075641X-ray source 0 0 4 1 ( 0)
    1204C 32.55278.76432.69643C 382Sy1 3 0 7 1 ( 0)
    121ESO 103-035279.585-65.4281Sy2 4 0 3 1 ( 0)
    122Kes 73280.331-4.936001E 1841-045Pulsar 2 0 4 1 ( 0)
    123SWIFT J1843.5-0343280.895-3.71600NULLTransient 0 67 855228 ( 4953)
    124AX J1846.4-0258281.602-2.97400AXJ1846.4-0258Pulsar 1 0 6 1 ( 0)
    1252CG 036+01283.1203.86700Gamma-ray source 0 0 3 1 ( 0)
    1262E 1853.7+1534284.00015.6369Sy1 1 0 7 1 ( 0)
    127ACO 2319290.18943.9619ABELL 2319Galaxy cluster 1 0 6 1 ( 0)
    128ESO 141-G55290.300-58.6670Sy1----
    129NGC 6814295.669-10.3240Sy1.5 2 58 453536 ( 6645)
    130KS 1947+300297.39030.21302MASS J19493548+3012317HMXB/NS 2 330 19556620 ( 3561)
    1312CG 065+00299.25028.80001CG 064+00Gamma-ray source 0 0 2 1 ( 0)
    132NGC 6860302.195-61.1000SWIFT J2009.0-6103Sy1----
    133IGR J20188+3647304.70036.7920NULLX-ray source 0 0 2 1 ( 0)
    1342CG 075+00305.33337.2530GRO J2021+37Gamma-ray source----
    135MCG +04-48-002307.14625.7336SWIFT J2028.5+2543Sy2 2 0 3 1 ( 0)
    1361RXS J202945.1+574348307.43857.7300NULLX-ray source 0 0 3 1 ( 0)
    137PSR J2032+41308.05841.3760NULLNULL----
    1384C 74.26310.65575.134087GB 204308.7+745733Sy1 2 0 8 1 ( 0)
    139Mrk 509311.041-10.7230MRK 509Sy1.2 4 0 3 1 ( 0)
    140IC 5063313.008-57.0692Sy1 2 0 2 1 ( 0)
    1412CG 095+04313.07555.2000Gamma-ray source 0 0 1 1 ( 0)
    142IGR J21117+3427317.94834.4620NULLX-ray source 0 31 353529 ( 6652)
    143S5 2116+81318.50582.0800XSS J21128+8216Sy1 1 0 2 1 ( 0)
    144RX J2135.9+4728323.97947.47312MASX J21355399+4728217Sy1 0 0 3 1 ( 0)
    145QSO B2149-306327.981-30.4649SWIFT J2152.0-3030Blazar 2 0 1 1 ( 0)
    146NGC 7213332.318-47.1668Sy1.5----
    147SAX J2224.9+5421336.21754.3650SAX2224.9+5421X-ray source----
    148NGC 7314338.942-26.0505Sy1.9 2 0 2 1 ( 0)
    149APG 319338.96633.9446NGC 7317Interacting galaxies 0 0 3 1 ( 0)
    1503C 452341.45539.687587GB 224331.7+392521Sy2 0 0 2 1 ( 0)
    151QSO B2251-179343.525-17.5820MR 2251-178Sy1 3 0 3 1 ( 0)
    152QSO B2300-189345.760-18.6903PKS 2300-18Sy1 0 50 253537 ( 6644)
    153NGC 7469345.8168.87386Sy2/LINER----
    154NGC 7582349.598-42.3710Sy2 2 0 2 1 ( 0)
    Source NameRA J2000 DegsDec J2000 DegsAlternate NameSource TypeToday#Yesterday#Tenday#Mean*Peak*Days*Last Day*
    # Explanation of table headings 7-9:
  • Today: Todays source rate in units of mCrab (Significance in parentheses)
  • Yesterday: Yesterdays source rate in units of mCrab (Significance in parentheses)
  • Tenday: Average source rate over the last ten days (Significance in parentheses)
  • All of these are only posted if the significance is >= 2-sigma.

    * Explanation of last four table headings:

  • Mean: Mean source rate in units of mCrab
  • Peak: Peak source rate in units of mCrab (also requires >5-sigma significance)
  • Days: Number of days with >5-sigma source detection
  • Last Day: MJD of last 5-sigma detection (Days since last detection)
  • Download the source catalog in FITS format (updated 08-Dec-2010): BAT catalog

    This page was last modified on Wed Sep 27 18:45:21 UTC 2023


    The BAT Transient Monitor contacts are:
    Amy Lien, amy.y.lien@nasa.gov,
    301.286.3624

    Hans Krimm, hans.krimm@nasa.gov,
    301-286-6955