1
2
3
Luminous Blue Variables OB SG G MS WD (Wikipedia) 4
<latexit sha1_base64="wz+byho7v8imoikzwcbr5jnmfci=">aaacanichvg7tgjbfd2sb3whnhoaimk OB G R136a1 (265 M ) http://www.eso.org/public/news/eso1030/ 5
<latexit sha1_base64="2bvcaa/swaae2t561b0ka5/il98=">aaacchichvhllgrbfd3t3um12egsnbmifppb3src2nhivayjk0l3t6gjp7t110zcxa/4aqsbjclim2z8givpedsknhbu9lrggvupurdo3xpvqsrds61aej3elkrqmtq6+oz4y1nzs2uirx0tcau+kdkma7v+hqehwryckzawtmwg5ws9b9hi3dibk5+vf4ufwk6zkg88kcnro461bzm6zcizmk2 <latexit sha1_base64="qh866bc6mkdoenmsgvgb9e1oxqu=">aaacchichvhllgrbfd3t3um12egsnbmifppb3ixe2nhivayjk0l3t6gjp7t110zcxa/4aqsbjclim2z8givpedsknhbu9lrggvupurdo3xpvqsrds61aej3elkrqmtq6+oz4y1nzs2uirx0tcau+kdkma7v+hqehwryckzawtmwg5ws9b9hi3dibk5+vf4ufwk6zkg88kcnro461bzm6zcizmk2 Structure of main sequence stars pp-chain reaction vs. CNO cycle l Stars with M<1.1M pp-chain reaction is dominant Core is in radiative equilibrium l Stars with M>1.1M CNO cycle is dominant Core is in convective equilibrium 6
Energy production rate is very sensitive to temperature in CNO cycle http://csep10.phys.utk.edu/astr162/lect/energy/cno-pp.html 7
<latexit sha1_base64="2bvcaa/swaae2t561b0ka5/il98=">aaacchichvhllgrbfd3t3um12egsnbmifppb3src2nhivayjk0l3t6gjp7t110zcxa/4aqsbjclim2z8givpedsknhbu9lrggvupurdo3xpvqsrds61aej3elkrqmtq6+oz4y1nzs2uirx0tcau+kdkma7v+hqehwryckzawtmwg5ws9b9hi3dibk5+vf4ufwk6zkg88kcnro461bzm6zcizmk2 Lower main sequence stars ( M<1.1M ) Convective envelope (large opacity) Radiative core (small temperature gradient) http://observe.arc.nasa.gov/nasa/space/ stellardeath/stellardeath_intro.html 8
<latexit sha1_base64="qh866bc6mkdoenmsgvgb9e1oxqu=">aaacchichvhllgrbfd3t3um12egsnbmifppb3ixe2nhivayjk0l3t6gjp7t110zcxa/4aqsbjclim2z8givpedsknhbu9lrggvupurdo3xpvqsrds61aej3elkrqmtq6+oz4y1nzs2uirx0tcau+kdkma7v+hqehwryckzawtmwg5ws9b9hi3dibk5+vf4ufwk6zkg88kcnro461bzm6zcizmk2 Upper main sequence stars ( M>1.1M ) Radiative envelope (small opacity) Convective core (large temperature gradient) 9
<latexit sha1_base64="wkhufqouzjssenalunkttnz7tys=">aaacdnichvhllgrbfd3t3um12egk0jezrca3vvkjgwssr0himeluhy6e7k53zqgtp+ahlmscbbgfyemhlhycwjkwshcnpwul3ervvxxqnntpvrmebqws6cgmvfrwvdfu1sxrgxqbmhmtruubm/dnktfd2/vxdd0qtu <latexit sha1_base64="u0qk5ymek+0nks/kwff+b6htphs=">aaacmxichvfntxrbeh2mirdysekfhmvedcqlm5qfvfseeiegembzigfg0zp0wmtnkz29m+bk/4b/werpmhbi/bmkxts7b36c8ygjfw/wzo5bd0h1uqv6db2q191o7hujjjobmg7cvdv4e2i4cgdkdgy8ehdim4naypv1n/ijte2irppekova077cjpuugepllaf1vhe+1zeq8ajwqx/fcjcqb6hx9fyhgwou520t2g07eppqbwnyne1yrbgotluphjuudnpls2xll52tlkvdrrfezcrm/cuokvx4owvaovjcbqtr8qq29hhbrrsbjejojn0ijdx2yieqm7alldhfk Mass luminosity relation of main sequence stars L M 3.5 n M L M 2.5 Massive stars are bright and live short 10
Surface magnetic fields l Lower main sequence stars Dynamo in convective envelope Complex field structures l Upper main sequence stars No dynamo in radiative envelope No magnetic fields in general, but fossil fields in some stars, where dipole component dominant 11
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What is a stellar wind? Stellar winds l a sustained outflow in the outer layers of a star, through which the star loses its mass continuously. l a source of mass, angular momentum, and energy to the interstellar matter. 13
<latexit sha1_base64="kyiux7x4re2pqwu6je6eeqjmdg0=">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</latexit> Stellar winds from solar-type stars Coronal winds: driven by gas pressure due to a high T in the corona (P corona >P ISM ) Coronal wind 2 10 6 K <latexit sha1_base64="jobtarjpuynptvlyflnlwgb8itg=">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</latexit> 6 10 3 K <latexit sha1_base64="xpfx7iguz5hka2vzgv4ipa/z+ww=">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</latexit> Corona heating Convective envelope 14
Isothermal coronal wind (Owocki 2004) 15
Solar wind (Wikipedia) 16
Stellar winds from massive stars Massive stars have high temperature (>10,000K), and hence high surface brightness. Light carries momentum as well as energy Radiation driven winds (Winds driven by the radiative force due to line absorption) 17
Winds driven by doppler-shifted line absorption Velocity thickness of layer of the resonance (Sobolev length) Wavelength Radius (Owocki 2001 in Encyclopedia of Astronomy and Astrophysics) 18
CAK theory (Castor, Abott, Klein 1975) continuum lines 19
Coronal winds vs. radiation driven winds Wind type Mass loss rate (km/s) (km/s) Coronal wind 10-14 400-700 100-200 Radiation driven wind 10-8 -10-4 1,000-3,000 10-30 (Owocki 2004) 20
Clumpy winds of massive stars v Radiation driven wind is unstable! CAK log (Owocki 2004) 21
<latexit sha1_base64="x9izloqvzhumjzpczy4ph1rscri=">aaacm3ichvfnsxxbeh1ojdfr1dw5biiwubgcgaxg+jeiaykxctn4tso4ssymvbun80vp74iz5g/kd+sqxbiiifgvkksgxj34e0kocl48phz2rhpqvnpd1a/rvb3qdmnfjproum+41x974m7g3dlqvegr0fly/y0kaitp1lzij9sw6ytcl6goaal9srur4qsulzbdvcxu/wzhqerg4brej8vo4drd2zceoxmql2ftwnetfark7m5npu1htdnukmdlbdwksnytx8tiugaz+dj8atxlfapsbuyvz4asf7owarvibyutr+wvslglcb7accaqqrpvw0hcyxswcdfjo0gzu+zj/f4gq4m <latexit sha1_base64="zh6ybuhvycjrcyt/gswuqfzb4cu=">aaacnhichvhlahrbfd1po8bxkve3ghaah4gbh9vxeq0iiwyhscapzxjih6g7uzntpppbdc1abpoh/aexkowcspazsngrllpij4qsi7hx4z2eduoieouqunxqnnvprfitjvndddrixri9eony2jxk1wvxb4xxb95qpnfpb6irxcrwa76xciuj0tdsklgwaogfvhkr/tblwf1qx+huxtebs52ijddrrlita88w1kpou6fnujrmfnutm7ntqrhju23tbzmru3ferk2zibnjpldf2a+dvrvgdsrm/sn5qs7zp47tlegnps3g1s9wsykyaxoiirdbsk/giewxdgeehlenzixp9mrxl5cjwtwerwmo8bjd4rxdp/us Clumpy structure of a massive star wind (1) r/r * red : log blue : log ini ini =+1 = 1 (Owocli & Sundqvist 2018) 22
Clumpy structure of a massive star wind (2) (Mellah et al. 2018) 23
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Be stars: early-type stars with a circumstellar disk l Definition Non-supergiant B-type stars, which once has shown Balmer lines in emission ( e is for emission) (Rivinius et al. 2013) (Martayan 2010) 25
Emission line profile vs. viewing angle (Rivinius et al. 2013) 26
Be/B much higher in SMC than in MW Population Metalicity effect? MW SMC (Martayan 2010) 27
<latexit sha1_base64="aac2ba93lhyjxds8jasx9c1xxbo=">aaacixichve9txtbeh0+qgigghmapdqndbgrgjuhcv9prlihnb82sbxyd5cfvr4v3a0twcl/gd9aqzviurslsrtagv4abt8hsglsmhsmzxclfcsz2p3zt/nm3u7aostjrxsv0/oe9d98ndcyhxoeetxaepk0hgetybe1j3cdamu2yufkx9suvk7ycinhebyrnu1mpxu+2rzrlan/qx2gysez9n25jx1lmdqote7xg5fuxtltddqdm1+anquoii9peuabulobzbidf41ckuqumv5x8jqmpxldnzkkimyqqeettlxdaactebdwoth2yshmsq0dhjcxhssmrrzj9fyggzxzw5w Two-component circumstellar envelope Polar wind l Low-density, fast (V r 10 3 km s 1 ) outflow emitting UV radiation l Wind structure well explained by line-driven wind model (Castor+ 1975) Equatorial disk l High-density region with optical emission lines and IR excess 28
Central star l Rapid rotation Conventional interpretation: ~70-80% of critical rotation Current idea: almost critical (~95% or more) increasing stellar rotation (Courtesy of Stan Owocki) 29
Disk formation mechanism Viscous decretion disk model by Lee, Saio & Osaki (1991) outward drift by viscosity mass ejection from star 30
Equatorial disk H =<latexit sha1_base64="2vcccnowlgq5axiflwzl2rtvzte=">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</latexit> Slow wind H Hydrogen spectrum l l Intensity Wavelength Courtesy of Stan Owocki 31
Formation and dissipation of circumstellar disks Mass injection: ON ang. mom. input Mass injection: OFF no ang. mom. input decretion accretion? Viscosity Nonradial MRI? pulsation? 32
1D simulations of circumstellar-disk formation and dissipation Formation Dissipation =0.1 <latexit sha1_base64="+v/qsuety4a+wm5rs+mi+gckv68=">aaacb3ichvhlssnafd2nr1pfvrckggslopty41tbklpxwvurghvj4qjbnaljwqjfh/addohcb4iin+hgh3dhj4gruxdjwts0oi7uo8zco2fuuffmjoayh =1 <latexit sha1_base64="is+bfh89aqsn2wtmupdrginwt0o=">aaacbxichvhlssnafd2nr1ofryogkbisplblpr4fqxtjslwr4gnj4qjbnaljwtdid7gwxiicgoj4 (Haubois+ 2012) 33
Estimated values of alpha in Be circumstellar disks (1) Photometric observations vs. 1D disk evolution model =0.1 1 <latexit sha1_base64="df5c/cxxav4emdu4cs15la7gzvy=">aaaccxichvhlssnafd2n7/qqulhcbisiiogmdbukgujgpa+q4iskjhqajifjc1r8ax9awzwcipgzbvwbf36cukzgxou3auvcqheyuxfo3hpvmrnds60gjhpose3nla1t7r3jzq7unt5ux/964jz9uxrm13b9tumphg05ohbaos02pv/ojcmwg0zxitrfqag/sfxnltz2xe5 (Ghoreyshi + 2018) 34
<latexit sha1_base64="gvcad5ddxfekpggbm7yi5q7ndf8=">aaacgnichvfnsxxbeh1onorgxdvebbgglabjyajdgdzvfeqvhv1afvxzesz2heydgwzmf3tx5m0/4cgnccksw/wjxvihcvaniecduxiwznzfpbir6e6q1/wqx3fzgxkjmoims3vx3fo+t68/82hg46fb7ndn9chvhi4so77yw01brfk5ni <latexit sha1_base64="d7o0uv2vp1lfsvli4khst29nnqy=">aaacgnichvfbsxtbfp6ytdamvdp2updc0qcih+vld4mxvbc99bi1ucfimf0nyejkd9ndbdt01fv/gadpfopib/unepepepanlb4vvptqt5uu0op6hpl575v3vflmnhmql06irnlao5hho0/gnuafpr+fmcy8elkrb93iltu3ueg05yhyks Estimated values of alpha in Be circumstellar disks (2) 54 Be stars from OGLE survey of SMC disk build-up phase =0.63 dissipation phase =0.26 bu (Rimulo + 2018) d <latexit sha1_base64="u3pbovhv9+whh/ze3a7qxfs7vme=">aaacdnich 35
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<latexit sha1_base64="baz+qgdbvbz/8vrgu+t8d1iesg4=">aaacenichvhlshxbfd3tvidrr0uq3dqoiiimt8dhjcsxgzecj4wkjgzdbanf9iuumgez5af8areudaqxfoab/eawfok4nodghxd6whix6i2q7q1t99x7qsqjpkk00u3gagvv6ozq7sl++njb158bgnxsys12rcknvtdecwwlpbmikpbaeztrlgzf8cs2u/3spn+ui1jjmpiqjyox59uhgtyqrq0 <latexit sha1_base64="vytrb5bxj5isntz47nc/3pdss48=">aaacenichvhllgrbfd3t3um1ieri0zehrdk57c1k2nhivaajkul3txkd/up3zsrm/iafslaiecfn2pgbc58gliq2fu70tgcbw6m6t07dc++pkso3rvaspsauuvqgxqbmlmrrw3thz6qrezp0soepsqzne8g2oyfctlyrlza0xbyfcn0xblflhcxwz7fkiggtz92qh77ydfsia+1zpi4zyqd6h5fvxffygqnqtjzpeqvpjurtacpqz Classification of X-Ray Binaries Low Mass X-ray Binaries (LMXB) Low mass star + NS/BH (M 1M ) Intermediate Mass X-ray Binaries (IMXB) High Mass X-ray Binaries (HMXB) high mass star + NS/BH (M 10M ) 37
<latexit sha1_base64="itiu1jarfrgyvwp+ec/ovkjksz8=">aaacehicsyriyswumtc4ycjezmlkxs7bycxnw8vhlyaoffacx1qunbqanj+txxsrlficmpozlxpaklmskxprujsamjuukxqelo0mkg8vsy0qzszpcympleinzu1mz8tmy0xol Distribution of X-ray binaries LMXB galactic bulge; globular clusters Old population (age > 10 9 yr) <latexit sha1_base64="rezimw6pns4sm4jnzzibcmntcse=">aaacehicsyriyswumtc4ycjezmlkxs7bycxnw8vhlyaoffacx1qunbqanj+txxsrlficmpozlxpaklmskxprujsamjuukxqelo0mkg8vsy0qzszpcympleinzu1mz8tmy0xol HMXB (Grimm et al. 2002) galactic disk Young population (age < 10 7 yr) 38
<latexit sha1_base64="baz+qgdbvbz/8vrgu+t8d1iesg4=">aaacenichvhlshxbfd3tvidrr0uq3dqoiiimt8dhjcsxgzecj4wkjgzdbanf9iuumgez5af8areudaqxfoab/eawfok4nodghxd6whix6i2q7q1t99x7qsqjpkk00u3gagvv6ozq7sl++njb158bgnxsys12rcknvtdecwwlpbmikpbaeztrlgzf8cs2u/3spn+ui1jjmpiqjyox59uhgtyqrq0 l l l Donor: low mass(m 1M ) Mass transfer: Roche lobe overflow Close & circular orbit Low mass donor Tauris & van den Heuvel (2003) LMXB Low-B NS or BH Accretion disk 39
<latexit sha1_base64="blnm2yyghz5mamuksa5t7qsiz2k=">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 l Sub-types: Ø Galactic disk LMXBs Ø Globular cluster LMXBs (by tidal capture/exchange encounter) Ø Soft X-ray transients Quiescence: 1~50 yr Outburst duration: months Luminosity: 10 32 erg/s 10 38 39 erg/s Ø millisecond X-ray pulsars 2019 8 19-23 40
Evolutionary Model for Low mass X-ray binaries ZAMS (Tauris & van den Heuvel 2003) RLO CE + spiral-in 41
SN NS LMXB ms PSR WD 42
<latexit sha1_base64="vytrb5bxj5isntz47nc/3pdss48=">aaacenichvhllgrbfd3t3um1ieri0zehrdk57c1k2nhivaajkul3txkd/up3zsrm/iafslaiecfn2pgbc58gliq2fu70tgcbw6m6t07dc++pkso3rvaspsauuvqgxqbmlmrrw3thz6qrezp0soepsqzne8g2oyfctlyrlza0xbyfcn0xblflhcxwz7fkiggtz92qh77ydfsia+1zpi4zyqd6h5fvxffygqnqtjzpeqvpjurtacpqz l HMXB Donor: high mass stars (M 10M ) Be stars or Supergiants l Compact object: high-b ( 10 12 G ) NS or BH <latexit sha1_base64="qoianmqm4rbcjetbe7j15psf0bs=">aaacghichvg7thtbfd0sb0paqines8jyrigcu+btygpfkhkzkdcxdpfbrnixdsewyowclh+gsausqhen+yy0/aafn4aojzqmra7xgwukyb3nzj1z77lz5o7h21yoir46lm6u7p7evv7uwochoeh l Mass transfer: Supergiants Be stars stellar wind or Roche-lobe overflow disk overflow 2019 8 19-23 43
Evolutionary Model for High mass X-ray Binaries ZAMS RLO He star SN NS (Tauris & van den Heuvel 2003) 44
HMXB CE + spiral-in He star RLO 2nd SN recycled PSR young PSR 45
Be/X-ray binaries Be disk NS or BH wide (10d<P orb <300d) & eccentric (e>0.3) orbit Overflow at periastron passage l l accretion (RIAF/slim disk?) transient X-ray emission Spin-up of NS during outbursts 46
Two types of X-ray outbursts in Be/X-ray binaries l l Type I (normal) outbursts Ø Periodic at P orb Often associated with Type II Biggest mystery Type II (giant) outbursts in Be/X-ray binaries Occasional; maybe quasi-periodic Be disk strongly deformed before/during Type II Ø Ø Ø Ø Ø (Stella+ 1986; Negueruela+ 1998) 47
Type I/II X-ray outbursts Type I (normal outbursts): Disk overflow at periastron Type II (giant outbursts): Mechanism unknown (taken from Bildsten et al. 1997) 48
Outburst times observed by BATSE (Bildsten et al. 1997) 49
Supergiant X-ray binaries Strong wind accretion X-rays high-b NS or BH Bondi-Hoyle-Lyttleton accretion Tauris & van den Heuvel (2003) 50
Two types of Supergiant X-ray binaries Persistent X-ray sources SG/X Transient X-ray sources SFXT (Supergiant Fast X-ray Transients) l l Has very brief outbursts, with a rise timescale of tens of min. and lasting only a few hours (Sguera et al. 2005). L X ~10 36 erg/s at outbursts, 10 33-35 erg/s otherwise (Sidoli et al. 2008) 51
Lightcurve of an SFXT during an outburst (Sidoli 2009, arxiv:0809.3157) 52
Clumpy winds in SGXB & SFXT? (Ducci et al. 2009) 53
SGXB vs. SFXT (Negueruela 2008) SGXB high clump density SFXT high clump density low clump density OBI OBI low clump density 54
HMXB population statistics in the Galaxy (Tauris+ 2017) Total number of HMXBs: 167 (~43% of all high-energy binaries in the Galaxy) BeXRB: 70 (42%) SG/X: 35 (21%) [SFXT: 12 (7%)] RLO: 3 (2%) unidentified: 59 (35%) (NB: Most HMXBs in SMC are Be/X-ray binaries) 55
Corbet Diagram Spin period (sec) SG/X (RLO) SG/X (wind) Be/X Orbital period (days) 56
(Tauris+ 2017) 57
Extended Corbet Diagram Spin period (sec) RLO SG/X (wind) DNS Be/X Orbital period (days) (Tauris+ 2017) 58
1) Tidal truncation 2) Tidal/radiative precession and warping 3) Kozai-Lidov mechanism 59
Interaction between the neutron star and the Be disk in Be/X-ray binaries NS/BH Be star Time-dependent accretion disk Truncated decretion disk with phasedependent structure 60
Observational support for tidal truncation l Correlation between Max{EW(H )} and in Be/X-ray binaries (Reig+ 1997) The longer the orbital period, the larger the maximum disk size 61
Reig (2011) 62
l Be disks denser in Be/X-ray binaries than in isolated Be stars (Zamanov+ 2001) Be disk Typical Be disks (Zamanov+ 2001) 63
Tidal truncation: Semi-analytial approach (Artymowicz & Lubow 1994; Negueruela & Okazaki 2001) l l Viscous torques provide angular momentum to the disk (Lin & Papaloizou 1986) Resonant torques remove angular momentum from the disk (Goldreich & Tremaine 1979, 1980) Criterion of disk truncation: T vis + T res < 0 at a resonance radius 64
65
Fourier components of potential 66
l Resonance radii The n:m resonance radius is the radius where =(n/m) orb <latexit sha1_base64="zybyjitnbdn97dee3y3fiaoxuci=">aaachxicsyriyswumtc4ycjezmlkxs7bycxnw8vhlyaoffacx1qunbqanj+txxsrlficmpozlxpaklmskxprujsamjuukxqelo0mkg8vsy0qzszpcympleinzu1mz8tmy0xolaekxqsoxpjnpqynkthq5onnaki48tg5isuzrbnv+uvjtfecygz6bmcggmqwntc0ndnumiskkdnaquc+whkggiyuhnygzizshlygviy8hhigo4chkaeyckmzdbkmgaqayrem1ucxiiareyyfyldlwaxuwwpulq At each resonance radius, there are three kinds of resonances 67
Resonant torques Outer and inner Lindblad resonances Corotation resonance 68
Viscous torque Criterion for resonant truncation 69
(Okazaki & Negueruela 2001) 70
71
Schematic diagram of Be disks in Be/X-ray binaries Viscous decretion disk truncated at a resonance radius (Negueruela & Okazaki 2001; Okazaki & Negueruela 2001) 72
Tidal truncation: Numerical approach Surface density evolution 73
Truncation radius decreases with increasing orbital eccentricity e = 0 e = 0.34 e = 0.68 (Also see Panoglou+ 2016) 74
Formation of a transient accretion disk in Be/X 75
1) Tidal truncation 2) Tidal/radiative precession and warping 3) Kozai-Lidov mechanism 76
Observational evidence for disk precession and warping Spectacular profile changes in 4U 0115+63 (Negueruela+ 2011; Reig+ 2007) 77
Interpretation of spectacular profile changes Precessing warped disk l l radiation-driven warping? (Pringle 1996; Porter 1998) tidal warping of a misaligned disk? (Martin+ 2011) (Negueruela+ 2001) 78
Disk precession and warping due to tidal torques An accretion disk inclined from binary orbital plane precesses at a(1 e 2 ) 1/2 P tidal / P orb q 1 r disk 3/2 (q 1). (Papaloizou & Terquem 1995) 79
<latexit sha1_base64="ou4r7of6qo0z4zpdkeu5dbs5yro=">aaacihichve9txtbeh0ccqenwq40kwhowi5swxnaqqcyncylx8awbgtdxraz8t6h7tawioufah8grsqquiqoakfowx+g4ccgspboumr8voikijnv7sy+ntfzdtcjlyw10dwimfrk6diz8ynm8xcvj7o5v1obcdcjxffxaxvenceohzk+qgiplaifkba9r4mq0/44ok92rrtlwn/qu <latexit sha1_base64="azwxskeyday59b/umczrhj/2dti=">aaacihichve9txtbeh0+eiamaqeasdsnwi5swxn8hjakksalpzbgwsi6u6ypffelu7ulcvipch+agiqroghr0cz1mvybfp4jkcvinbsmz4diciez2p3zt/nm3u5aostjrttiarmphk5ott/kzzx+mjtxedq/hqfdybyno3cdamcyy+fkxzsuvk7ycsnhepyrmtbb2+f5syeiwab+l <latexit sha1_base64="ernhpwtvnnniqjvp/ioiml45thq=">aaacphichvhlahrbfd1px3f8znsn4kzxsigujrdh81aqgy50ozbkmkkgkztvnzpjkx5rxtmqm/4bf8cfk4ug4mdke3brfvkecrnbjqvv9lsvrfqwvffwqxvupvxljyfkddhrihxq9jmz50bpvy5cvhr5rhrl6koa97qvw34cxhrne6kmvcrbrplarivaital5kq383hwvtqxolvxtgx2e7krim6kosoxhig3+tc47vcybr1milddklcftdta+fm7qbqhscef2m/d27a+tzk5u408z5z/5ru1ledutuz1ksz+i5gm596myzsluknpc3h1hdryqgwfpysqiga4dicq8liha0lc2ayyxjrhqjixyffhbo+zjgcirnd47fjuvuqj3g9qpgxb5y4bt81mg+n0so/pma7oa t align t align Tidal warping (Lubow & Ogilvie 2000; Martin+ 2011) Tidal torques have alignment effect on a tilted disk toward the orbital plane. (GM r)1/2 t align = T tid t vis : Disk aligns with orbital plane t vis : Disk moves towards orbital plane if it doesn t completely align 80
1) Tidal truncation 2) Tidal/radiative precession and warping 3) Kozai-Lidov mechanism 81
KL mechanism in hydrodynamical disks (Martin+ 2014) Kozai Lidov (KL) oscillations occur in highly misaligned [ (Fu+ 2015)] disks, where disk inclination is periodically exchanged for disk eccentricity (Kozai 1962; Lidov 1962; Martin+ 2014; Fu+ 2015). KL oscillations are damped oscillations in viscous disks (Martin+ 2014; Fu+ 2015). 82
Initially circular disk can become highly eccentric with the exchange of inclination No mass injection from star in this sim (Martin+ 2014) 83
KL oscillation decays relatively quickly due to the effect of viscosity e Period of KL cycle: for a test particle i (Martin+ 2014) 84
85
l 3D SPH Numerical setup l Artificial viscosity parameters, which roughly corresponds to shear viscosity parameter l Be star s rotation axis misaligned with the binary orbit plane by toward apastron ( ) l Constant mass injection from stellar equatorial region l Target: 4U 0115+634 (P orb =24.3d, e=0.34), which shows quasi-periodic giant outbursts. 86
Tearing of Be disk in 4U0115+634 Be disk, once developed, is torn near the base by tidal torque. This triggers cyclic disk evolution P orb =24.3 d, e=0.34, i disk =45 deg. about y-axis (=semi-minor axis) Column density along z-axis Density in orbital plane 87
Cyclic evolution of misaligned Be disks in Be/X-ray binaries Initially circular disk becomes eccentric by the Kozai-Lidov mechanism. When tidal torque becomes stronger than mass-addition torque, disk is torn near the base and starts precession. Gap opens between the disk base and mass ejection region. New disk forms in the stellar equatorial plane. 88
Observational implications of cyclic Be-disk evolution l Long-term (~7 yr in this sim for 4U0115+634) variations in: Ø accretion rate over a wide range (> 10), which might be a cause of giant X-ray outbursts, Ø disk brightness due to the change in density and size of emitting region as well as disk orientation, Ø line profiles (equivalent width, peak separation, ratio between two peaks). l Appearance of a double-disk feature in line profiles. 89
Does this mechanism explain giant outbursts? l l Due to propeller effect, X-ray outbursts are likely to occur only for high mass-transfer rate from Be disk. Decrease in disk emission precedes X-ray active stage. Consistent with observations associated with giant outbursts variations in accretion rate and Be-disk mass 90
Simulation Evidence for double Be-disk? X Per Appearance of two sets of double-peaked line Clark+ 2001; Nakajima+ 2019) 91
92
Ground-based VHE gamma-ray astronomy Imaging Atmospheric Cherenkov Telescopes (H.E.S.S., VERITAS, and MAGIC) Discovery of >100 VHE gamma-ray (E > 100 GeV) sources H.E.S.S. 93
VHE (TeV) gamma-ray sources l Supernova remnants l Pulsar wind nebulae l Massive binaries l Gamma-ray bursts l Active galactic nuclei 94
(VHE) gamma-ray binaries l Binaries with spectral energy distribution (SED) dominated by gamma-ray emission l Only 7 confirmed systems and 1 candidate: Ø 4 systems with a Be star Ø 3 systems with an O star l Nature of compact object established only for 2 systems (both have a non-accreting pulsar) l Two competing scenarios for other systems: Pulsar wind scenario vs. Microquasar scenario 95
High energy emission in PW scenario Collision shocks between a relativistic pulsar wind and a stellar wind (and/or a Be disk) Acceleration of electrons synchrotron radio, X-rays IC gamma-rays 96
High energy emission in MQ (accretion/ejection) scenario Accretion Relativistic jet Leptonic model: IC by relativistic electrons gamma-rays Hadronic model: pp interactions neutral pions gamma-rays 97
System Compact object Companion Porb e LS 5039? O 3.9 d 0.35 LMC P-3? O 10.3 d 0.4 1FGL J1018.6-5856? O 16.6 d low LS I +61 303? Be 26.5 d 0.54 HESS J0632+057? Be 321 d 0.83 PSR B1259-63 pulsar Be 3.4 yr 0.87 PSR J2032+4127 pulsar Be 48 yr 0.98 98
Comparison between HMXBs and gamma-ray binaries Number of systems >100 7 X-ray Strong (thermal) Weak (nonthermal) Gammaray Optical companion No detection Be stars, OB supergiants Strong Be stars, MS-O stars 99
Evolutionary link between HMXBs and gamma-ray binaries? Conventional idea based on PW scenario Spin down of pulsar Gamma-ray binaries HMXBs very young systems with rapidly rotating pulsars Magnetar GB? Transitional (No) supergiant GBs? populations? Systems with flip-flopping pulsars? Slowly rotating, accreting pulsars 2019 8 19-23 100
Dynamic modeling of gamma-ray binaries Relativistic simulations of collision between stellar wind and pulsar wind (Bosch-Ramon+ 2015) 101
Density distributions at t=2.6, 2.9, 5.2, and 5.85d 102
Dynamic modeling of gamma-ray binaries with Be stars l l l l l 3D SPH simulations with Spherically symmetric stellar and pulsar winds Relativistic pulsar wind (PW) is modeled by a highvelocity (10 4 km/s), non-relativistic wind with the same momentum flux. Optically-thin radiative cooling Target systems Ø PSR B1259-63: P orb =3.4 yr, e=0.87 Ø PSR J2032+4127: P orb =48 yr, e=0.978 103
PSR B1259-63 (O9.5e + 49ms pulsar; P orb =3.4 yr, e=0.87) (Okazaki+ 2011, Takata, Okazaki+ 2012) X-ray flux peaks at disk transit (Chernyakova+ 2015) 104
<latexit sha1_base64="gozqmf8ib0vz+tzg+kyz+eeeoz0=">aaacjhichvhlshxbfd22xseyoknuatk0dmowirfj+azcqcc49duq2gbolstjyb/orhnqwr8qxgervqihbjduk5wb/eawfok4vhctre70tggwjre PSR J2032+4127 (B1e+143 ms pulsar; P orb =48 yr, e=0.978) (Coe, Okazaki+ 2019) X-ray flux goes down when pulsar is in Be-disk shadow 105
Comparison between model and observed X-ray light curves Model Periastron X-ray flux Observation (Coe, Okazaki+ 2019) 106