NuSTAR will continue both Galactic and Extragalactic Legacy Surveys during the extended mission, with programs selected based on community input. The legacy survey data will be immediately made public, and source catalogs and spectra will be released as soon as they have been processed. The legacy surveys listed below have been chosen to be observed during NuSTAR General Observer (GO) cycle-4 and 5 periods (2018-2020).
Last updated: 2019/02/04
Two of NuSTAR’s key mission goals were to conduct deep, wide-field surveys in both Galactic and extragalactic fields. While a significant amount of time has already been invested in these surveys during the baseline mission, it is clear that maximizing the legacy of the NuSTAR satellite will require significantly extending both of these surveys.
The Legacy Survey programs have been designed in consultation with the community, while the detailed observations are planned, scheduled, and executed by the NuSTAR science team. This team has the expertise and the experience in the intricacies of such observations – e.g., avoiding stray light from (transient) bright sources, scheduling repeat observations to minimize roll angle changes, optimal background subtraction, and source identification. Legacy survey data have no exclusive use period, and are executed by the NuSTAR science team as a service to the community. Importantly, while some Legacy programs are expected to be fully executed, other programs provide lists of filler/snapshot targets, observed as they fit within the schedule and with no expectation that the entire sample is observed.
Legacy Survey Manifest
Survey |
Number of Targets |
Total Exposure (ks) |
Extragalactic |
||
XMMLSS | 6 | 300 |
XBootes | 6 | 300 |
SDSS Stripe 82 | 21 | 1050 |
Seyfert type-1 AGN | 15 | 800 |
Swift-BAT AGN | 6 / month | 20 each |
NuLANDS | 29 | 990 |
EHT coordination | 3 |
220 |
Obscured Seyfert AGN | 9 | 270 |
Galactic and Nearby Galaxies |
||
Swift Galactic plane survey | ToO | 75 each |
Swift SMC transients (S-CUBED) | ToO | 50 each |
Galactic center molecular clouds | 2 | 450 |
Intermediate Polars / WD mass | 25 | 1020 |
Cosmic X-ray Background |
200 |
|
Solar hard X-ray corona monitoring |
90 |
Legacy Survey Target list (ASCII file)
One of the principal goals of the NuSTAR extragalactic surveys is to constrain the high-energy X-ray luminosity function and trace its evolution as a function of redshift and AGN obscuration. In previous years, we pursued a multi-layer survey strategy, ranging from ultra-deep observations of selected fields (e.g., ECDFS, EGS, and COSMOS) to shallow observations of wider areas identified through serendipitous source detections.
In 2017 and 2018, most of the extragalactic survey observations consist of targeted observations of interesting sources, useful both for studying those sources and for continuation of the serendipitous program.
1) Deeper exposures around sources discovered in three sky surveys, XMMLSS, XBootes, and SDSS stripe 82. 50 ks exposures for each position are planned for 2017-2018 (Total 1650 ks), observed on a best-effort basis.
ObsID | Name | J2000 (deg) | |
RA | Dec | ||
60364001 | XMMLSS_001 (1) | 34.592333 | -5.103950 |
60364002 | XMMLSS_002 * | 35.067750 | -4.078042 |
60364003 | XMMLSS_003 * | 34.912833 | -5.192706 |
60364004 | XMMLSS_004 | 35.741583 | -4.311372 |
60364005 | XMMLSS_005 (1) | 34.454208 | -5.385211 |
60364006 | XMMLSS_006 | 36.457375 | -4.006881 |
60365001 | XBootes_001 * | 218.934000 | 35.076178 |
60365002 | XBootes_002 | 216.189500 | 33.244019 |
60365003 | XBootes_003 | 216.348750 | 35.473378 |
60365004 | XBootes_004 * | 217.551875 | 33.244361 |
60365005 | XBootes_005 * | 217.841083 | 34.679581 |
60365006 | XBootes_006 | 217.448583 | 35.574303 |
60366001 | S82X_001 (2) | 43.800917 | -0.183547 |
60366002 | S82X_002 * | 352.614000 | -0.683503 |
60366003 | S82X_003 | 351.926917 | -0.754672 |
60366004 | S82X_004 * | 334.374542 | 0.818278 |
60366005 | S82X_005 * | 25.624042 | -0.598903 |
60366006 | S82X_006 | 20.000708 | -0.371197 |
60366007 | S82X_007 | 19.128708 | 0.451014 |
60366008 | S82X_008 | 18.387708 | 0.496672 |
60366009 | S82X_009 | 18.157958 | 0.086319 |
60366010 | S82X_010 * | 16.595375 | -0.355475 |
60366011 | S82X_011 | 16.528833 | 0.340319 |
60366012 | S82X_012 | 16.153333 | -0.297100 |
60366013 | S82X_013 | 13.859375 | 0.605947 |
60366014 | S82X_014 * | 46.175292 | -1.053886 |
60366015 | S82X_015 * | 54.075375 | 0.542350 |
60366016 | S82X_016 | 24.925583 | -0.105264 |
60366017 | S82X_017 | 20.922750 | 0.743306 |
60366018 | S82X_018 | 13.870125 | 0.581256 |
60366019 | S82X_019 | 352.343625 | -0.928497 |
60366020 | S82X_020 * | 353.071958 | 0.277431 |
ObsID | Name | J2000 (deg) | Exposure | |
RA | Dec | (ks) | ||
60376001 | 2MASX J19301380+3410495 | 292.557500 | 34.180500 | 50 * |
60376002 | Mrk 463 | 209.011749 | 18.371469 | 50 |
60376003 | 1RXS J034704.9-302409 | 56.772099 | -30.3978 | 50 * |
60376004 | SDSS J104326.47+110524.2 | 160.860300 | 11.090100 | 50 |
60376005 | Mrk 1393 | 227.224800 | -0.197000 | 50 |
60376006 | 3C 309.1 | 224.781600 | 71.672200 | 50 * |
60376007 | UGC 06728 | 176.316800 | 79.681500 | 50 * |
60376008 | 2MASX J03540948+0249307 | 58.53950 | 2.82520 | 50 |
60376009 | 1RXS J055229.5+592842 | 88.11710 | 59.47690 | 50 |
60376010 | 2MASX J05580206-3820043 | 89.50830 | -38.33460 | 50 |
60376011 | IRAS 05589+2828 | 90.54460 | 28.47170 | 50 |
60376012 | NVSS J062335+644538 | 95.89640 | 64.76010 | 50 * |
60376013 | 2MASS J07594181-3843560 | 119.92420 | -38.73220 | 50 |
60376014 | 2MASX J22484165-5109338 | 342.17160 | -51.16500 | 50 |
60376015 | MCG +02-57-002 | 335.93800 | 11.83600 | 50 |
60376016 | 2MASX J23013626-5913210 | 345.40100 | -59.22250 | 50 |
3) Swift-BAT detected AGN (20 ks each)
Observations of extragalactic sources taken from the Swift BAT hard X-ray survey will continue in 2017-2018. Each target will be observed for 20 ks by NuSTAR and 7 ks by Swift-XRT. On average 6 sources are observed each month. Previously the 70-month Swift BAT catalog was used for NuSTAR targeting. In 2017, the sample was increased to include new sources detected in the 105-month survey.
A higher priority is assigned to the subset of these targets that are scheduled for Chandra observations as part of the Chandra Cool Attitude Target program starting in January 2019.
4) NuLANDS: Representative IRAS-selected AGN sample (total 990 ks)
The distribution of obscuring column densities is a key observational boundary condition for models of AGN evolution and the cosmic X-ray background. The NuSTAR Local AGN N_H Distribution Survey (NuLANDS) will observe a representative sample of 30 IRAS-selected AGN hosts at z<~0.04 to study their gas column densities, and to understand the AGN-galaxy connection.
Each target will also be contemporaneously observed by Swift to obtain 7 ks XRT exposures.
ObsID | Name | J2000 (deg) | Exposure | |
RA | Dec | (ks) | ||
60360002 | NGC 0449 | 19.0300485 | 33.0893489 | 30 * |
60360003 | IC 4995 | 304.995765 | -52.621908 | 30 |
60360004 | UGC 01214 | 25.990757 | 2.349857 | 30 * |
60360005 | 2MASX J01500266-0725482 | 27.5112236 | -7.4301471 | 30 |
60360006 | Mrk 1239 | 148.0795705 | -1.6120791 | 20 |
60360007 | KUG 0312+013 | 48.7722605 | 1.5083828 | 30 |
60360008 | SDSS J152132.21+391206.9 | 230.3874232 | 39.2007671 | 20 * |
60360009 | FAIRALL 0265 | 104.1241396 | -65.5604616 | 20 |
60360010 | MCG-02-08-039 | 45.1276199 | -11.4158391 | 30 * |
60361011 | 2MASXJ 15504152-0353175 | 237.6729079 | -3.8883412 | (40) |
60361012 | CGCG 498-038 | 358.9343387 | 30.2123336 | 40 * |
60361013 | UGC 10120 | 239.7901018 | 35.0298614 | 25 * |
60361014 | IC 1198 | 242.151567 | 12.3310191 | 25 * |
60361015 | MRK 0315 | 346.0109554 | 22.6242896 | 25 |
60361016 | KUG 1021+675 | 156.304361 | 67.2971854 | 40 * |
60361017 | ESO 344-G016 | 333.6750623 | -38.8063487 | 25 * |
60361018 | KUG 0135-131 | 24.5224744 | -12.8695399 | 40 |
60361019 | CGCG 004-040 | 127.5600721 | -2.8805107 | 40 |
60361020 | FGC 0061 | 8.6812072 | -0.0407954 | 40 |
60361021 | SBS 1426+573 | 217.0749075 | 57.1718086 | 40 * |
60361022 | 2MASX J03241196-5750116 | 51.0498478 | -57.8367233 | 40 |
60361023 | UGC 09944 | 233.9486961 | 73.450724 | 30 * |
60362024 | CGCG 166-047 | 235.9888601 | 28.5239359 | 40 # * |
60362025 | 2MASX J21391374-2646315 | 324.8071404 | -26.7754607 | 40 # * |
60362026 | 2MASX J03381036+0114178 | 54.5432269 | 1.238402 | 40 # * |
60362027 | 2MASX J02560264-1629159 | 44.0110223 | -16.4876579 | 40 # |
60362028 | CGCG 077-080 | 230.2218089 | 8.3968659 | 40 # |
60362029 | ESO 018-G009 | 126.0329349 | -77.7825942 | 30 # * |
60362030 | IRAS 03362-1641 | 54.6398049 | -16.5384568 | 40 # |
ObsID | Name | J2000 (deg) | Exposure | |
RA | Dec | (ks) | ||
30502005 | Sgr A* | 266.416837 | -29.007811 | 4 x 20 a |
60502010 | M87 | 187.705830 | 12.391110 | 2 x 20 a |
30502006 | Sgr A* | 266.416837 | -29.007811 | 4 x 25 b |
ObsID | Name | J2000 (deg) | Exposure | |
RA | Dec | (ks) | ||
60465001 | Mrk 334 | 0.7901 | 21.96025 | 30 |
60465002 | UM 146 | 28.841738 | 6.611703 | 30 |
60465003 | NGC 3362 | 161.215515 | 6.596915 | 30 * |
60465004 | UGC 6100 | 165.391679 | 45.653786 | 30 |
60465005 | NGC 5256 | 204.5742 | 48.2781 | 30 |
60465006 | NGC 5283 | 205.273896 | 67.67215 | 30 * |
60465007 | Mrk 461 | 206.824125 | 34.148864 | 30 * |
60465008 | Mrk 471 | 215.730775 | 32.850572 | 30 * |
60465009 | NGC 5929 | 231.525658 | 41.670667 | 30 * |
NuSTAR is allowing us to probe more deeply into the Galaxy than ever before. The goals of these surveys are to expose the hidden Milky Way and reveal the wide range of astrophysics that creates high-energy emission. NuSTAR studies of flares from Sgr A* probing the physical conditions in the immediate vicinity of the nearest supermassive black hole. By studying high-mass X-ray binaries (HMXB) in a range of environments, we can learn about their formation soon after a supernova event and determine the fraction of HMXBs with black holes. The latter is important for answering questions about HMXB evolution, such as how many neutron star/black hole binaries exist, which has important implications for future gravity wave experiments. In addition to point source studies, NuSTAR is also investigating diffuse emission toward the Galactic Center, including the Galactic ridge emission and the time variation of the reflected emission from dense molecular clouds that probe the accretion history of Sgr A*. The coordinates and characteristics of any transient discovered will immediately be broadcast to the community via electronic circulars such as the Astronomer’s Telegram.
There are seven survey programs approved for observations in 2017 and 2018:
1) Swift Galactic Plane Survey Key Project - NuSTAR observations of sources identified during the Swift Galactic plane survey (Multiple targets, 500 ks total). Observations will continue up to 2019-06-01.
ObsID |
Name |
J2000 (deg) |
Exposure |
|
RA |
Dec |
(ks) |
||
30360001 |
Swift J1843.5-0343 |
280.89481 |
-3.71571 |
75 * |
30360002 |
Swift J183920-045350 |
279.833750 |
-4.897139 |
40 * |
ObsID |
Name |
J2000 (deg) |
Exposure |
|
RA |
Dec |
(ks) |
||
30361001 |
SXP 59.0 |
13.7340833 |
-72.4466389 |
50 * |
30361002 |
SXP 15.3 |
13.05825 |
-73.321889 |
2 x 75 * |
30361003 |
Swift J005139.2-721704 |
12.913375 |
-72.28433 |
75 * |
ObsID |
Name |
J2000 (deg) |
Exposure |
|
RA |
Dec |
(ks) |
||
40113001 |
Sgr A Molecular Cloud |
266.4747 |
-28.9013 |
2 x 150 * |
40401001 |
Sgr B2 |
266.8350 |
-28.385278 |
150 # |
4) Survey of Intermediate Polars (total 1020 ks)
Intermediate Polars (IP) are binary systems in which matter from a main sequence companion is accreted along magnetic field lines onto the poles of a magnetic white dwarf (WD). This systematic survey of 25 IPs selected from the Swift-BAT 70 month catalog aims to measure the masses of the WDs and constrain the mass distribution of these magnetic cataclysmic variable systems.
ObsID | Name | J2000 (deg) | Exposure | |
RA | Dec | (ks) | ||
30460001 | 1RXS J21334.1+510725 | 323.43179 | 51.12353 | 25 * |
30460002 | FO Aqr | 334.48075 | -08.35108 | 25 * |
30460003 | V2400 Oph | 258.15175 | -24.24581 | 25 |
30460004 | V1432 Aql | 295.04758 | -10.42383 | 25 * |
30460005 | IGR J17195-4100 | 259.89833 | -41.01514 | 25 * |
30460006 | XY Ari | 44.034104 | 19.442811 | 30 * |
30460007 | V405 Aur | 89.49708 | 53.89581 | 30 * |
30460008 | AO Psc | 343.82496 | -03.17778 | 35 * |
30460009 | PQ Gem | 117.822179 | 14.739972 | 35 |
30460010 | BY Cam | 85.70333 | 60.85872 | 35 * |
30460011 | EI Uma | 129.59167 | 48.6339 | 35 |
30460012 | V667 Pup | 113.15683 | -13.51925 | 40 |
30460013 | IGR J15094-6649 | 227.35837 | -66.82314 | 40 * |
30460014 | IGR J16500-3307 | 252.481842 | -33.117250 | 40 |
30460015 | V1062 Tau | 75.61450 | 24.75644 | 40 |
30460016 | IGR J16547-1916 | 253.682317 | -19.275228 | 45 |
30460017 | IGR J04571+4527 | 74.279133 | 45.463447 | 45 |
30460018 | BG CMi | 112.87088 | 09.93975 | 45 * |
30460019 | V515 And | 13.8329 | 46.2158 | 50 |
30460020 | 1RXS J052523.2+241331 | 81.34479 | 24.22597 | 55 |
30460021 | RX J2015.6+3711 | 303.90400 | 37.18978 | 55 * |
30460022 | YY Dra | 175.8958 | 71.7033 | 55 * |
30460023 | V2069 Cyg | 320.93675 | 42.30047 | 60 |
30460024 | IGR J14536-5522 | 223.42108 | -55.36075 | 60 * |
30460025 | IGR J08390-4833 | 129.70462 | -48.52356 | 60 * |
Cosmic X-ray Background (CXB) (200 ks)
The cosmic X-ray background (CXB) was discovered over 50 years ago, and represents an important integral of the total accretion power of supermassive black holes. However, despite many attempts to measure its spectrum, the normalization of the spectrum at ~3-20keV has considerable uncertainty. In this legacy survey we plan to use the Moon as a shutter, enabling a clear and unambiguous measurement of the CXB to be made with NuSTAR. During the observation we will track the Moon while it oscillates, due to parallax, over 4 degrees of sky. An exposure of 200ks is sufficient to achieve our goal of measuring the normalization and spectral shape of the CXB.
Solar hard X-ray corona monitoring (90 ks)
The Sun currently is entering its minimum period of activity, with the absolute minimum expected to occur in about 2019, and global Solar activity will be monitored by NuSTAR through this period. An investigation of the solar-cycle variability of the global corona will be a novel and important scientific achievement. NuSTAR's spectral coverage makes it the most sensitive instrument ever for the detection of temperature variations and non-thermal bremsstrahlung/free-bound emission.
During this part of the cycle, the shear zones of the solar torsional oscillations, which relate globally to magnetic flux emergence, will jump from low latitudes to high latitudes according to the well-established Babcock-Leighton pattern. The NuSTAR observations can relate this to global coronal temperature variations for the first time. At 3 keV, relative to a greybody spectrum at kT < 0.1 keV, we would expect a 30-fold amplification of the temperature dependence: d(ln S)/d(ln T) ~ 30, where S is the spectral flux at 3 keV. This implies very powerful leverage on possible plasma temperature variations in the quiet corona, which NuSTAR mosaic imaging can characterize globally. In addition to thermal emission processes there is the possibility of non-thermal signatures associated with coronal heating (e.g., nanoflares or with cosmic-ray secondary products). This investigation will also contribute to other ongoing science priorities: the study of quiet Sun microflares (which also have an unknown variation through this part of the cycle) and the search for an axion signal from Sun center.
Two orbit mosaic maps of the Sun will be obtained at approximately three month intervals.
Interested in providing feedback about the Legacy Surveys? We are now activiely soliciting input from the community. Please give us your thoughts!