Isolated Neutron Stars for ART, eROSITA and LOBSTER Sergei Popov (SAI MSU) http://www.sparavigna-video-graphic.com/foto%20singole/observer.htm Observer

Good old classics The pulsar in the Crab nebula A binary system

The new zoo of neutron stars During last 10 years it became clear that neutron stars can be born very different. In particular, absolutely non-similar to the Crab pulsar. Compact central X-ray sources in supernova remnants. Anomalous X-ray pulsars Soft gamma repeaters The Magnificent Seven Unidentified EGRET sources Transient radio sources (RRATs) ….

Main reviews NS basics: physics/0503245 SGRs & AXPs: astro-ph/0406133 !!!! Recent observations AXPs astro-ph/0610304 SGRs astro-ph/0608364 Theory of magnetars: astro-ph/0504077 Central compact X-ray sources in supernova remnants: astro-ph/0311526 The Magnificent Seven: astro-ph/0609066 !!!! RRATs: astro-ph/0608311 Cooling of NSs: astro-ph/0508056 !!!!

Wanted! There are several types of uncatchable compact objects which still are not detected: Isolated accreting NSs Isolated BHs Isolated NSs on the Propeller stage NSs in the galactic halo Extragalactic magnetars Also we want to detect more cooling INSs. Finally, there are several interesting types of accreting binaries, which can be detected: Massive NS accreting from WDs Accreting magnetars (including magnetors)

Evolution of NSs. I.: temperature [Yakovlev et al. (1999) Physics Uspekhi] First papers on the thermal evolution appeared already in early 60s, i.e. before the discovery of radio pulsars.

Evolution of neutron stars. II.: rotation + magnetic field Ejector → Propeller → Accretor → Georotator 1 – spin down 2 – passage through a molecular cloud 3 – magnetic field decay astro-ph/0101031 See the book by Lipunov (1987, 1992)

Isolated NS Census Rather conservative evolutionary scheme was used. For example, supersonic propellers have not been considered (Ikhsanov 2006). astro-ph/9910114

Accreting isolated NSs At small fluxes <10-13 erg/s/cm2 accretors can become more abundant than coolers. Accretors are expected to be slightly harder: 300-500 eV vs. 50-100 eV. Good targets for eROSITA! From several hundreds up to several thousands objects at fluxes about few X 10-14, but difficult to identify. Monitoring is important. Also isolated accretors can be found in the Galactic center (Zane et al. 1996, Deegan, Nayakshin 2006). astro-ph/0009225

Young cooling radio dim NSs Source Period, s RX 1856 7.05 RX 0720 8.39 RBS 1223 10.31 RBS 1556 6.88? RX 0806 11.37 RX 0420 3.45 RBS 1774 9.44 The Magnificent seven Radio quiet (?) Close Young Thermal emission Spectral features Long periods Poster by Malofeev

More cooling NSs eROSITA has better sensitivity for sources with T>200 eV. We expect that there are more INS in the directions towards OB associations. These INS are younger and hotter than the Magnificent Seven. eROSITA can find few dozens.

Known magnetar candidates AXPs CXO 010043.1-72 4U 0142+61 1E 1048.1-5937 CXOU J164710.3- 1 RXS J170849-40 XTE J1810-197 1E 1841-045 AX J1844-0258 1E 2259+586 SGRs 0526-66 1627-41 1806-20 1900+14 +candidates

SGRs and AXPs

Are SGRs and AXPs brothers? Bursts of AXPs Spectral properties Quiescent periods of SGRs (0525-66 since 1983) Gavriil et al. 2002

AXPs: bursts and transients Typical bursts of SGR 1806-29, SGR 1900+14 And of AXP 1E 2259+586 detected by RXTE (from Woods, Thompson astro-ph/0406133)

SGRs: monitoring and extraG SRG detectors can contribute to observations of SGRs. [D. Frederiks et al. astro-ph/0609544]

Compact central X-ray sources in supernova remnants Cas A Puppis A

RRATs: also young coolers? Rotating Radio Transients have been discovered recently (McLaughlin et al. 2005). They can represent a very numerous population of NSs. One of RRATs is identified in Chandra data as a young cooling NS. Slightly hotter than the Magnificent seven (Reynolds et al. 2006).

Unidentified EGRET sources Grenier (2000), Gehrels et al. (2000) Unidentified sources are divided into several groups. One of them has sky distribution similar to the Gould Belt objects. Search in 56 EGRET error-boxes resulted in no PSR detections (Crawford et al. 2006). GLAST (and, probably, AGILE) can help to solve this problem. eROSITA and LOBSTER also can contribute.

Проект Джильда-Гала Проект в основном создается учеными МИФИ (Институт Космофизики) Солнечно-синхронная круговая орбита Высота орбиты 835 км Наклонение 98.68 градуса Чувствительность от 10 МэВ Большое поле зрения Хороший тайминг Запуск 2010 год Срок работы 5-7 лет Мониторинг неба в гамма-лучах

Isolated BHs Isolated BHs can be detected due to accretion or due to some exotic emission. Punsly et al. (astro-ph/0007465) predict that some of EGRET unidentified sources can be isolated BHs. Corresponding X-ray luminosity is about 1033-1034 erg/s. astro-ph/0511224

Massive NS accreting from WDs Observations of very massive NSs are important for EOS studies. Probably, most massive NSs cannot be observed as radio pulsars. astro-ph/0412327

Binaries with magnetars - magnetors Can RCW 103 be a prototype? 6.7 hour period (de Luca et al. 2006) Possible explanations: Magnetar, spun-down by disc Double NS system Low-mass companion + magnetar= magnetor RCW 103

Conclusion There are several types of sources: CCOs, M7, SGRs, AXPs, RRATs ... Unsolved problems: 1. Are there links? 2. Reasons for diversity Detectors on-board SRG can contribute in discovery of new INS and other interesting objects

Main reviews NS basics: physics/0503245 SGRs & AXPs: astro-ph/0406133 Magnetars: Observations AXPs astro-ph/0610304 SGR astro-ph/0608364 - Theory astro-ph/0504077 Central compact X-ray sources in supernova remnants: astro-ph/0311526 The Magnificent Seven: astro-ph/0609066 RRATs: astro-ph/0608311 Cooling of NSs: astro-ph/0508056 Труды ГАИШ том 72 (2003) http://xray.sai.msu.ru/~polar/sci_rev/ns.html

Dorothea Rockburne (www.bradcovington.com)

Magnetorotational evolution of radio pulsars Spin-down. Rotational energy is released. The exact mechanism is still unknown.

Known AXPs Sources Periods, s CXO 010043.1-72 8.0 4U 0142+61 8.7 6.4 CXOU J164710.2- 10.6 1RXS J170849-40 11.0 XTE J1810-197 5.5 1E 1841-045 11.8 AX J1845-0258 7.0 1E 2259+586

What is special about magnetars? Link with massive stars There are reasons to suspect that magnetars are connected to massive stars. Link to binary stars There is a hypothesis that magnetars are formed in close binary systems (astro-ph/0505406). Westerlund 1 The question is still on the list.

Close-by radio quiet NSs Discovery: Walter et al. (1996) Proper motion and parallax: Kaplan et al. No pulsations Thermal spectrum Later on: six brothers RX J1856.5-3754

27 Dec 2004 Giant flare SGR 1806-20 Spike 0.2 s Fluence 1 erg/cm2 E(spike)=3.5 1046 erg L(spike)=1.8 1047 erg/s Long «tail» (400 s) P=7.65 s E(tail) 1.6 1044 erg Distance 15 kpc

SGRs: periods and giant flares P, s Giant flares 0526-66 1627-41 1806-20 1900+14 8.0 5 March 1979 (?) 6.4 18 June 1998 7.5 27 Dec 2004 5.2 27 Aug 1998 New result: oscillations in the “tail”. “Trembling” of the crust (Israel et al. 2005, Watts and Strohmayer 2005). See the review in Woods, Thompson astro-ph/0406133

Anomalous X-ray pulsars Identified as a separate group in 1995. (Mereghetti, Stella 1995 Van Paradijs et al.1995) Similar periods (5-10 sec) Constant spin down Absence of optical companions Relatively weak luminosity Constant luminosity