Hunting for the missing spiders and TeV
emissions from globular clusters andGalactic black hole binaries
Albert Kong
Institute of Astronomy
National Tsing Hua University, Taiwan
On behalf of the Fermi Asian Network (FAN)TeV Observations of Globular Clusters• Is the TeV emission associated with Ter 5?
• The TeV centroid is 4 arcmin from the centre of Ter 5, way outside the half-mass radius• It is marginally within the tidal radius of the GC• The TeV emission is extended

Prospects of CTA•
Basedon
H.E.S.S.
observations:•Case study: Ter 5

0.44-24 TeV photon flux =-12-2-1
1.2x10 cm s (1.5% of Crab)Ter 5

From Hassan+ 2016, CTA Consortium MeetingWhat about LST only?

Ter 5

GeV/TeV Emission of Galactic Black Hole Binaries• Cyg X-3: AGILE (Tavani+ 2009), Fermi/LAT (2009)• Cyg X-1: Fermi/LAT (Zanin+ 2016)• V404 Cyg: Fermi/LAT (Loh+ 2016); very marginal detection• V404 Cyg is the only low-mass X-ray black hole binary• The observed gamma-rays are all associated with radio flux, indicating an origin related torelativistic jets and shocks• Is jet the only mechanism to generate gamma-rays?
• The discovery of TeV emission from the radio galaxy IC 310 (Aleksic+ 2014) casts doubt on jetrelated models. The observed parameters are not consistent with models.

• TeV emission could also be from a black hole gap arising in the polar funnel of a rotating BH
magnetosphere (Beskin+ 1992; Hirotani & Okamoto 1998; Hirotani+ 2016)

Black Hole Gap Emission• Unlike jet-related model, black hole gap model
requires a black hole transient in quiescence.

• Very low accretion rate
• A radiatively inefficient accretion flow cannot provide
enough photons to maintain a force-freemagnetosphere via two-photon collisions• In this charge-starved magnetosphere (BH gap), an

electric field inevitably arises along the magnetic field
line to accelerate electrons and positrons into ultrarelativistic energies.

Hirotani+ in prep.

• Large BH mass and spin

Lin+ 2017

Spiders: Black Widows and Redbacks• MSPs in compact binary systems• P < 1 day• Radio eclipses due to evaporating materials from the companion• Some show X-ray, optical (including colour), and gamma-ray modulation• Black Widows• Very low mass (< 0.05 M ) companions• Redbacks• Higher mass (> 0.1 M ) non-degenerate companions• Can show state transitions (MSP LMXB)orb⊙⊙

Spider MSPs
• Pulsar radiation can ablate the companion, leaving an isolated MSP at the end• They are important systems to study the evolution and formation of MSPs
• Before the launch of Fermi in 2008, there are only 3 BW MSPs found out of> 100 MSPs.

volume 1 . number 3 . pages 253–380

men quality

male odour: effects
p statusfemale orgasmic

tormale satin
narrow downeen–male andmale damselflies

marsupialin suicidal mating

brains get smallernn

ise ins, C. Marquez,nary history of then, R. C. Fleischer,wind farm

D. M. Evans, S. M. Redpath, S. A. Evans, D. A. Elston &P. Dennis

326 Genetic diversity predicts pathogen resistanceand cell-mediated immunocompetence in house
finches
330 Continental variation in relative hippocampal volume
in birds: the phylogenetic extent of the effect and thepotential role of winter temperatures
L. Z. Garamszegi & J. R. Lucas

334 Feathers at nests are potential female signals in thespotless starling
J. P. Veiga & V. Polo

338 Why not walk faster?
J. R. Usherwood

342 Modulation of passive force in single skeletal
muscle fibres
D. E. Rassier, E.-J. Lee & W. Herzog

346 Do insect metabolic rates at rest and during flightscale with body mass?
J. E. Niven & J. P. W. Scharlemann

350 Epidemiological implications of the contact
network structure for cattle farms andthe 20–80 rule

M. E. J. Woolhouse, D. J. Shaw, L. Matthews, W.-C. Liu,
D. J. Mellor & M. R. Thomas

353 Different hunting strategies select for different
weights in red deer

M. Martínez, C. Rodríguez-Vigal, O. R. Jones, T. Coulson &A. San Miguelvisible to birds

362 Effects of Hurricane Charley on fish chorusing

M. N. Dean, C. D. Wilga & A. P. Summers
J. V. Locascio & D. A. Mann

366 Extreme spatial variability in marine picoplankton
and its consequences for interpreting Eulerian
time-series
A. P. Martin, M. V. Zubkov, P. H. Burkill & R. J. Holland

rostructures in the370 Habitat selection determines abundance, richness
and species composition of beetles in aquaticcommunities

kadees: features

375 Costly parasite resistance: a genotype-dependent
handicap in sand lizards?

M. L. Spetch &oncentrations ofblhe Royal Society
scientific academyd to promotingce

No 207043

pages 253–380

D. M. Hawley, K. V. Sydenstricker, G. V. Kollias &A. A. Dhondt

berstein

dip and plunge

number 3

322 Livestock grazing affects the egg size of an
insectivorous passerine

357 Eating without hands or tongue: specialization,
elaboration and the evolution of prey processing
mechanisms in cartilaginous fishes

ggests a mechanisms

volume 1

C. A. Binckley & W. J. Resetarits Jr

M. Olsson, E. Wapstra, T. Madsen, B. Ujvari & C. Rugfelt

378 Differential sex allocation in sand lizards: bright males
induce daughter production in a species withheteromorphic sex chromosomes
M. Olsson, E. Wapstra & T. Uller

volume 1 . number 3 . pages 253–380 . 22 September 2005

e in England 500
in Britain

Biology Letters

22 September 2005

ISSN 1744-9561

www.journals.royalsoc.ac.uk
Published in Great Britain by The Royal Society,
6–9 Carlton House Terrace, London SW1Y 5AG

22 September 2005

Credit: NASA

Unidentified Fermi Objects (UFOs)
as Spider MSPs
• Traditionally, MSPs are found with radio timing.
• Selection effects of radio biased the sample.
• Timing in a compact system is difficult• Absorption and scattering in BW/RB is enormous• Radio plane survey• Usually discovered in globular clusters• Fermi has changed the game
• Radio/gamma-ray timing on Fermi sources• > 200 gamma-ray PSRs; nearly 100 MSPs; > 30 spidersHui et al. 2015

Unidentified Fermi Objects (UFOs)
as Spider MSPs
Linares+ 2017

Fermi

Li+ 2016

New BWs/RBs from UFOs
• 2FGL J1311.7-3429 = PSR J1311-3430 (Romani 2012)• 1FGL J0523.5-2529 (Strader+ 2014)
2FGL
J2039.6-5620(Romani2015;Salvetti+2015)•3FGL
J1544-1125(Bogdanov&Halpern2015;tMSPcandidate)•3FGL
J1048.6+2338=PSR
J1048+2339(Deneva+2016)•• 3FGL J0212.1+5320 (Li+ 2016; Linares+ 2017)• 3FGL J0838.8-2829 (Halpern+ 2017)
SeealsoHui+2015
andSalvetti+2017forothercandidates•

PSR J2339.7-0533

Optical/X-ray @4.6hrFermi

Irradiation onthe companion

Pulsarmagnetosphere

Intra-binaryshock
Kong+ 2012

Heating on the companion’s surface

Romani et al. 2011

Companion’s Mass of BWs and RBs

BWs
Softer spectra

RBs
Harder spectra

Chen et al. 2013

PSR J1723-2837

PSR J2129-0429
Hui+ 2015

X-ray light curve profiles allow us tomodel the intra-binary shock(Romani+ 2016)
Kong+ 2017

NuSTAR (3-79 keV) Observations of Spiders
PSR J2129-0429
Kong+ in prep.

PSR J1023+0038
Li+ 2014•

Non-thermal emission
is seen as a power-law
up to ~50 keV• The spectrum of RB
PSR J1723-2837
Kong+ 2017(Γ~1.3) is harder thanthat of BW (Γ>2). Lee+submitted (see alsoDavid’s talk)• Is it due to different
contribution ofshocks?

Multi-wavelength Synergy and Beyond• Gamma-ray data with X-ray/optical identification play a key role insearching missing MSPs when radio pulsation search fails. There
are still many UFOs. Radio-faint isolated MSPs?

•AreBWandRB
twodistinct
populations?
Sameevolutionpath?
•TheFermiBWs/RBs
havetheshortest
orbitalperiods
andhighest•
The X-ray spectrum of RBs is harder than that of BWs. Why?

NS masses• Optical/X-ray data are crucial in constraining the NS mass
• Equation of State; mass gap of NS/BH• TeV observations will allow us to study the shock physics