Papers to read for exams etc. 1. physics/ Baym, Lamb "Neutron stars" 2. astro-ph/ Lattimer, Prakash "Physics of neutron stars" Weber et al. "Neutron stars interiors and equation of state of superdense matter" Reisenegger "Neutron stars and their magnetic fields« 5. astro-ph/ Popov “The zoo of neutron stars” (to be continued up to 15 items....)

Lecture 2. Isolated Neutron Stars. Intro. Sergei Popov (SAI MSU)

Prediction... Neutron stars have been predicted in 30s: L.D. Landau: Star-nuclei (1932) + anecdote Baade and Zwicky: neutron stars and supernovae (1934) (Landau) (Baade) (Zwicky)

Some historical remarks (from a lecture by Dmitrii Yakovlev)

Shapiro,Teukolsky (1983) (from lectures by D. Yakovlev)

Rosenfeld L In: Astrophysics & Gravitation, Proceeding of the 16 th Solvay Conference on Physics, Brussels, Belgium, p. 174

Gordon Baym (2000)

Physikalische Zeitschrift der Sowjetunion Vol. 1, No. 2, , 1932 Written: Feb. 1931, Zurich Received: Jan. 7, 1932 Published: Feb Landau paper BEFORE neutron discovery

S. Chandrasekhar. The maximum mass of ideal white dwarfs, ApJ 74, 81, 1931 (submitted: Nov. 12, 1930) E.C. Stoner, Phil. Mag. 9, 944, 1930 Necessary to violate quantum mechanics

This is correct! Disappered in reprints, so we have difficulties

Baade and Zwicky – theoretical prediction W. Baade (Mt. Wilson Observatory) F. Zwicky (Caltech) The meeting of American Physical Society (Stanford, December 15-16, 1933) Published in Physical Review (January 15, 1934)

Phys. Rev. 46, 76, 1934 July 1

Los Angeles Times January 19, 1934 A.G.W. Cameron, recalling his postdoc academic year at Caltech reminds (Cameron, 1999): “For years Fritz [Zwicky] had been pushing his ideas about neutron stars to anyone who would listen and had been universally ignored. I believe that the part of the problem was his personality, which implied strongly that people were idiots if they did not believe in neutron stars.”

Good old classics The pulsar in the Crab nebula A binary system For years two main types of NSs have been discussed: radio pulsars and accreting NSs in close binary systems

The old zoo of neutron stars In 60s the first X-ray sources have been discovered. They were neutron stars in close binary systems, BUT they were «not recognized».... Now we know hundreds of X-ray binaries with neutron stars in the Milky Way and in other galaxies.

Rocket experiments Sco X-1 Giacconi, Gursky, Hendel 1962 In 2002 R. Giacconi was awarded with the Nobel prize.

UHURU The satellite was launched on December 12, The program was ended in March The other name SAS keV The first full sky survey. 339 sources.

Accretion in close binaries Accretion is the most powerful source of energy realized in Nature, which can give a huge energy output. When matter fall down onto the surface of a neutron star up to 10% of mc 2 can be released.

Accretion disc The theory of accretion discs was developed in by N.I. Shakura and R.A. Sunyaev. Accretion is important not only in close binaries, but also in active galactic nuclei and many other types of astrophysical sources.

Close binary systems About ½ of massive stars Are members of close binary systems. Now we know many dozens of close binary systems with neutron stars. L=Mηc 2 The accretion rate can be up to g/s; Accretion efficiency – up to 10%; Luminosity –thousands of hundreds of the solar.

Discovery !!!! 1967: Jocelyn Bell. Radio pulsars. Seredipitous discovery.

The pulsar in the Crab nebula

Isolated neutron stars population: in the Galaxy and at the backyard  INSs appear in many flavours  Radio pulsars  AXPs  SGRs  CCOs  RINSs  Local population of young NSs is different (selection) Radio pulsars Geminga+ RINSs

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

Compact central X-ray sources in supernova remnants Cas ARCW 103 New result: 6.7 hour period (de Luca et al. 2006) Problem: small emitting area

Puppis A One of the most famous central compact X-ray sources in supernova remnants. Age about 3700 years. Probably the progenitor was a very massive star (mass about 30 solar). New results: V kick =1500 km/s WinklerWinkler, Petre 2006 Petre (astro-ph/ )

Magnetars dE/dt > dE rot /dt By definition: The energy of the magnetic field is released P-Pdot Direct measurements of the field (Ibrahim et al.) Magnetic fields –10 15 G

Known magnetars SGRs candidates AXPs CXO U E CXOU J RXS J XTE J E AX J E (СТВ 109)

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

Transient radio emission from AXP (Camilo et al. astro-ph/ ) Radio emission was detected from XTE during its active state. One another magnetar was reported to be detected at low frequencies in Pushchino, however, this result has to be checked.

Another AXP detected in radio 1E P= 2 sec SNR G

Transient radiopulsar PSR J P=0.3 sec B= G , The pulsar increased its luminosity in X-rays. Magnetar-like X-ray bursts.

ROSAT ROentgen SATellite Launched 01 June The program was successfully ended on 12 Feb German satellite (with participation of US and UK).

Close-by radioquiet NSs Discovery: Walter et al. (1996) Proper motion and distance: Kaplan et al. No pulsations Thermal spectrum Later on: six brothers RX J

Magnificent Seven NamePeriod, s RX RX RBS RBS ? RX RX RBS Radioquiet (?) Close-by Thermal emission Absorption features Long periods

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. It is suggested that GLAST (and, probably, AGILE) Can help to solve this problem. Actively studied subject (see for example papers by Harding, Gonthier) New results: no radio pulsars in 56 EGRET error boxes (Crawford et al. 2006)

Radio pulsars (Kuiper et al. astro-ph/ ) Crab nebula spectrum Crab pulsar spectrum

Pulsars invisible in radio? (Grenier astro-ph/ )

Binaries with radio pulsars (Aharonian et al. astro-ph/ , see also Kirk et al. astro-ph/ ) PSR B Cutoff at 5 Mev depends on the model of electron injection

Discovery of radio transients McLaughlin et al. (2006) discovered a new type of sources– RRATs (Rotating Radio Transients). For most of the sources periods about few seconds were discovered. The result was obtained during the Parkes survey of the Galactic plane. These sources can be related to The Magnificent seven. Thermal X-rays were observed from one of the RRATs (Reynolds et al. 2006). This one seems to me the youngest.

P-Pdot diagram for RRATs McLaughlin et al Nature Estimates show that there should be about Sources of this type in the Galaxy. Young or old??? Relatives of the Magnificent seven? (astro-ph/ )

RRATs 11 sources detected in the Parkes Multibeam survey (McLaughlin et al 2006) Burst duration 2-30 ms, interval 4 min-3 hr Periods in the range s Period derivative measured in 3 sources: B ~ G, age ~ Myr RRAT J detected in the X-rays, spectrum soft and thermal, kT ~ 120 eV (Reynolds et al 2006)

RRATs P, B, ages and X-ray properties of RRATs very similar to those of XDINSs Estimated number of RRATs ~ 3-5 times that of PSRs If τ RRAT ≈ τ PSR, β RRAT ≈ 3-5 β PSR β XDINS > 3 β PSR (Popov et al 2006) Are RRATs far away XDINSs ?

RRATs. Recent data (arXiv: ) X-ray pulses overlaped on radio data of RRAT J

Calvera et al. Recently, Rutledge et al. reported the discovery of an enigmatic NS candidated dubbed Calvera. It can be an evolved (aged) version of Cas A source, but also it can be a M7-like object, who’s progenitor was a runaway (or, less probably, hypervelocity) star. No radio emission was found.

Conclusion There are several types of sources: CCOs, M7, SGRs, AXPs, RRATs... Magnetars (?) Significant fraction of all newborn NSs Unsolved problems: 1. Are there links? 2. Reasons for diversity

Main reviews NS basics: physics/ physics/ astro-ph/ SGRs & AXPs: astro-ph/ CCOs: astro-ph/ Quark stars: astro-ph/ The Magnificent Seven: astro-ph/ astro-ph/ RRATs: astro-ph/ astro-ph/ Cooling of NSs: astro-ph/ astro-ph/ astro-ph/ NS structure astro-ph/ EoS astro-ph/ NS atmospheres astro-ph/ Some recent results astro-ph/