Very-High-Energy (TeV) Observations of Pulsar Wind Nebulae and Supernova Remnants Nukri Komin University of the Witwatersrand Johannesburg, South Africa Nukri Komin 9th International Fermi Symposium (2021) 1 PWNe and SNRs in a Nutshell possible binary systems black holes supernova explosion isolated neutron stars of massive star rotating neutron star core contraction → pulsar rotation driven 28 38 e surrounded by electron wind Ė 10 ...10 erg/s xp (C) A Hitchhikers Gui an → pulsar wind nebula de to Space and Pla si sma Physics on o f o ut er composites la ye rs kinetic SN energy warf explosion supernova type Ia white d supernova remnant ~1051 erg Nukri Komin 9th International Fermi Symposium (2021) 2 TeV Instruments ➲ ground based observations of atmospheric showers ➲ Imaging Air Cherenkov Telescopes → Cherenkov light in air → small field of view, low-duty cycle → detailed studies of individual sources → H.E.S.S., MAGIC, VERITAS ➲ Extensive Air Shower Arrays → direct detection of shower particles → large field of view, large duty cycle → population studies, large sources → Cherenkov light in water tanks (HAWC) → scintillation counters (Tibet Air Shower Array) Nukri Komin 9th International Fermi Symposium (2021) 3 Hubble (NASA/ESA) Crab Nebula: TeV Observation Timeline ➲ 1989, Whipple [Weekes et al. 1989 ApJ v.342, p.379] → 9σ detection, >0.7 TeV ➲ 1996, HEGRA [HEGRA Collaboration 1996 APh v. 4-3, p. 199-215] H.E.S.S. 2006 → 10σ detection, 1-3 TeV, power law spectrum ➲ 2003, Milagro [Atkins et al. ApJ v. 595, Issue 2, pp. 803-811] → 3 6.4σ, 4 TeV median energy 186 MAGIC >25 GeV ➲ 2006, H.E.S.S. [H.E.S.S. Collaboration, A&A, v. 457-3, pp.899-915] 185 → ~100σ, 440 GeV – 40 TeV, spectral cut-off 184 ➲ 2008, MAGIC [MAGIC Collaboration, ApJ v. 674-2, p. 1037-1055] 183 -1 -0.5 0.501 → 60 GeV – 9 TeV, curved power law Phase ➲ pulsed emission → 2008, MAGIC [MAGIC Collaboration, Science, Volume 322, Issue 5905, pp. 1221] → 2011, VERITAS [VERITAS Collaboration, Science 334: 69] ➲ > 100 TeV photons → 2019, Tibet [Amenomori et al. PhysRevL, v. 123, Issue 5, id.051101] → 2019, HAWC [HAWC Collaboration ApJ, Volume 881, Issue 2, article id. 134] ➲ 2020, H.E.S.S. [H.E.S.S. Collaboration, NatAs Volume 4, p. 167-173] → extension ➲ many other publications and instruments (CTA prototypes, ...) [MAGIC, JHEAp, Volume 5, p. 30-38.] Nukri Komin 9th International Fermi Symposium (2021) 4 Crab Nebula ➲ PSR B0531+21 → P = 33.4 ms, Ṗ =4.2×10-13, Ė = 4.5×1038 erg/s, age ~1000 years → d = 2 kpc [MAGIC, JHEAp, Volume 5, p. 30-38.] ➲ gamma-ray luminosity → 50 GeV – 30 TeV → 1035 erg/s (0.02% Ė) ➲ Why is it so bright in TeV? → 2nd most luminous pulsar → point-like source ● X-ray extension 50’’ (0.5 pc) → strong synchrotron emission → SSC Nukri Komin 9th International Fermi Symposium (2021) 5 Crab Nebula with H.E.S.S. ➲ [HESS 2020, Nat. Astron,, v, 4, p. 167-173] ➲ increase angular resolution → simulate detector response on run-by-run basis → account for detector problems, night-sky-background, ... → 0.05° (68% containment) X C M h ➲ a 1.0 - 3.0 TeV Electrons Crab extension 52’’ (1σ of Gaussian) a M n d U 3.0 - 10.0 TeV Electrons r a −7 V 10 W 10.0 - 30.0 TeV Electrons H 1 . → E smaller than in UV . S . S ) −8 . 1 10 − → significantly larger than in X-rays s 2 − −9 m 10 c ➲ g H.E.S.S. probes electron energies r e −10 ( 10 ν that are not well observed in F synchrotron emission ν 10−11 10−12 10−7 10−4 10−1 102 105 108 1011 1014 Energ (eV) Nukri Komin 9th International Fermi Symposium (2021) 6 HESS J1825–137 ➲ [HESS 2019, A&A 621, A116] ➲ PSR B1823–13 → Ė = 2.8×1036 erg/s, age 21 kyrs → d ~ 4 kpc ➲ PWN at TeV → ~0.8° (~56 pc) ● larger than X-ray nebula (15’) [Uchiyama et al., PASJ 2009, v.61, pp.S189] ● larger than 1-100GeV nebula (0.56°) [Grondin et al 2011 ApJ 738 42] → L = 3.1×1035 erg/s = 11% Ė Nukri Komin 9th International Fermi Symposium (2021) 7 HESS J1825–137 ➲ energy dependent morphology → highest energy electrons do not travel too far away from pulsar → >16 TeV photons come only from X-ray nebula Table 3. Extent measurements as a function of energy for analyses A and B, with statistical and systematic errors. Energy range Extent (A) Extent (B) <1 ! "e# $ %.37◦ ±%.15◦ ±%.3◦ 1 !− !% "e# $ %.63◦ ±%.%&◦ ±%.%&◦ < !% "e# %.''◦ ±%.%(◦ ±%.3◦ $ !%−!%% "e# %.&'◦ ±%.03◦ ±%. ◦ %.71◦ ±%.%)◦ ±%.01◦ !%% "e#−1 Te# %.& ◦ ±%.% ◦ ±%.%!◦ %.& ◦ ±%.%!◦ ±%. ◦ 1− Te# %.'(◦ ±%.% ◦ ±%.11◦ %.' ◦ ±%.%&◦ ±%.(◦ −( Te# %.(&◦ ±%.%(◦ ±%.%*◦ %.51◦ ±%.%!◦ ±%.1◦ (−* Te# %.38◦ ±%.%(◦ ±%.13◦ %.33◦ ±%.%&◦ ±%.%(◦ *−16 Te# %. &◦ ±%.%&◦ ±%.%'◦ %.30◦ ±%.12◦ ±%.3◦ >16 Te# $ %. ◦ ±%.12◦ ±%. ◦ 16−32 Te# %.19◦ ±%.%*◦ ±%.14◦ $ X-ray nebula >32 Te# %.14◦ ±%.1◦ ±%.%!◦ $ Nukri Komin 9th International Fermi Symposium (2021) 8 Particle Transport in HESS J1825–137 ) o ➲ energy dependent diffusion ( ! t n e → size would increase with energy t 1 $ E ! l a ➲ diffusion and cooling # d a → maximum extend at energy where cooling " time meets age ● Ee = 4 TeV, B ≈12 μG (BX-rays ≈5 μG) → nebula becomes smaller with energy ➲ advection So%th!& South!' → nebula confined by ISM δ 10-1 EDGE (0 → nebula even smaller than for diffusion EDGE δ(1 Fit!&nal sis & ➲ energy-dependent morphology allows F#t!&nal sis B )#+%s#on the study of the particle transport Advection → more prominent at larger distance from 10-1 1 10 pulsar Energy!TeV Nukri Komin 9th International Fermi Symposium (2021) 9 TeV J2032+4130 VERITAS ➲ first unidentified and extended TeV source → HEGRA [A&A, v.431, p.197-202 (2005)] → Whipple [A&A, v.423, p.415-419 (2004)] → MAGIC [ApJL, Volume 675, Issue 1, pp. L25 (2008)] → VERITAS [ApJ, Volume 783, Issue 1, article id. 16, 9 pp. (2014)] ➲ PSR J2032+4127 → Ė = 1.5×1035 erg/s, age 2×105 years, distance 1.3 kpc ➲ nebula → TeV extension 9.5’ × 4.0’ (3.6 pc × 1.5 pc), L ~ 0.3% Ė → X-ray extension 12’ → good PWN candidate ➲ binary system on 50-years orbit → detected at periastron by VERITAS and MAGIC ● [ApJL, Volume 867, Issue 1, article id. L19, 8 pp. (2018)] → orbit < 200 AU MAGIC → binary system inside a PWN (?) Nukri Komin 9th International Fermi Symposium (2021) 10 TeV PWN Population 20 PSRs > 1034 erg/s/kpc 2 Randomised PSRs > 1034 erg/s/kpc 2 15 N 10 5 ➲ PWN in the H.E.S.S. Galactic Plane Survey 0 0.0 0.5 1.0 1.5 2.0 → [A&A, Volume 612, id.A2, 25] Squared Angular Distance PSR-TeV [deg 2] 28 34 2 → 140 PSRs 10 - 10 erg/s/kpc correlation between pulsar and TeV emission Randomised PSRs 1028 - 1034 erg/s/kpc 2 for Ė/d2 > 1034 erg/s/kpc2 120 100 80 → 14 firmly identified PWN N 60 → 18 PWN candidates 40 20 0 0.0 0.5 1.0 1.5 2.0 Squared Angular Distance PSR-TeV [deg 2] Nukri Komin 9th International Fermi Symposium (2021) 11 TeV PWN Population r yr ky ➲ -11 1 k 0 young, high-Ė pulsars 10 Kes 75 1 MSH 15-52 yr ➲ exception -12 0 k 10 10 Crab Nebula CTA 1 → PSR B1742−30 3C 58 r ] Vela X ky 1 -13 00 − 10 J1825-137 10 33 s N157B ● Ė = 8.5×10 erg/s s [ ● 5 e τ = 5.5×10 years t -14 s a 10 / g R r e ● 9 d = 200 pc n 3 0 w 1 o -15 → d 10 2 candidate TeV sources - n i ● p very small: 0.2°, 0.06° S -16 /s 10 g r ● e unlikely PWN candidates 7 3 Firm identifications 0 1 -17 Candidate PWNe 10 /s /s g g PWNe outside HGPS r r e e 5 3 3 3 ATNF pulsars 0 0 10 -18 1 1 10 -2 10 -1 10 0 10 1 Period [s] Nukri Komin 9th International Fermi Symposium (2021) 12 TeV PWN Population 10 2 ➲ efficiency: Firm identifications 10 1 Candidate PWNe PWNe outside HGPS Lim its → 0 Ė of pulsar at present time 10 Varied Model ˙ E / V Baseline Model → e L1-10TeV from electrons injected over T -1 0 1 10 − J1825-137 life time of pulsar 1 L y -2 c 10 ➲ efficiency grows with age n e MSH 15-52 i c i N157B CTA 1 f f -3 Kes 75 e 10 V e T -4 Vela X 10 Crab Nebula 10 -5 3C 58 10 -6 10 0 10 1 10 2 Characteristic age τc [kyr] Nukri Komin 9th International Fermi Symposium (2021) 13 TeV PWN Population ➲ offset of pulsar from TeV 10 2 emission centroid J1825-137 ➲ increases with age N157B 10 1 ] → proper motion of pulsar c MSH 15-52 CTA 1 p [ t Kes 75 3C 58 Vela X → e inhomogeneous medium leads to s f f o 0 asymmetric (“crushed”) PWN 10 r Crab Nebula a s l u P Firm identifications Candidate PWNe -1 10 PWNe outside HGPS Min. offset (0.0056 deg) at 5.1 kpc Max. offset (0.5 deg) at 5.1 kpc 500 km /s 10 -2 10 0 10 1 10 2 Characteristic age τc [kyr] Nukri Komin 9th International Fermi Symposium (2021) 14 TeV PWN Population Firm identifications 10 3 ➲ extension of nebula Candidate PWNe PWNe outside HGPS increases with age Varied Model Baseline Model ] c p 2 N157B [ 10 N W P R J1825-137 n o i s n e MSH 15-52 t 1 x 10 e CTA 1 V 3C 58 e Crab Nebula T Kes 75 Vela X on teracti hock in n rse s o reve si n a 0 p 10 x e e e fr 10 0 10 1 10 2 Characteristic age τc [kyr] Nukri Komin 9th International Fermi Symposium (2021) 15 Composite Supernova Remnants ➲ radio/X-rays: PWN and SNR shell visible ➲ HESS J1554–550 → pulsar not identified Chandra X-rays → TeV emission smaller then shall [Temim et al., ApJ 2015, 808, 100] → most likely PWN emission ➲ HESS J1119–614 → PSR J1119−6127, Ė = 2.3×1036 erg/s → d = 8.4 ± 0.4 kpc → emission from PWN or shell? Nukri Komin 9th International Fermi Symposium (2021) 16 Supernova Remnants and Cosmic Rays up to 1015 eV ➲ Are SNRs the sources of Galactic CRs (protons) up to 1015 eV? → is the emission hadronic? → what is the cut-off of the spectrum? AB IC 443 W44 10-10 10-10 ) ) 1 1 - - s s / / - - m m c c ! ! g g r -11 r -111 e 10 e 10 ( ( ! ! E E d d 1 1 0 0 d Best-fit!3ro4en!5o6er la6 d / / Best-fit!3ro4en!5o6er la6 Ferm#-7&T E VE"8T&S!( ) E Ferm#-7&T -1/ M&*8C!( ) -1/ &*87E!( ) 10 &*87E!( ) 10 π0-deca π0-deca Bremsstrahl%ng Bremsstrahl%ng Bremsstrahl%ng!6#th!'rea4 Bremsstrahl%ng!6#th!Brea4 10- 10.