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Stars with Special Characteristics Sp.-V/AQuan/1999/10/12:16:09 Page 397 Chapter 16 Stars with Special Characteristics J. Donald Fernie 16.1 Variable Stars ........................ 398 16.2 Cepheid and Cepheid-Like Variables .......... 399 16.3 Variable White Dwarf Tables .............. 400 16.4 Long-Period Variables .................. 406 16.5 Other Variables ...................... 406 16.6 Rotating Variables ..................... 407 16.7 T Tauri Stars ........................ 408 16.8 Flare Stars ......................... 409 16.9 Wolf–Rayet and Luminous Blue Variable Stars .... 410 16.10 Be Stars ........................... 413 16.11 Characteristics of Carbon-Rich Stars .......... 415 16.12 Barium, CH, and Subgiant CH Stars .......... 416 16.13 Hydrogen-Deficient Carbon Stars ............ 417 16.14 Blue Stragglers ....................... 418 16.15 Peculiar A and Magnetic Stars ............. 419 16.16 Pulsars ............................ 420 16.17 Galactic Black Hole Candidate X-Ray Binaries ... 422 16.18 Double Stars ........................ 424 397 Sp.-V/AQuan/1999/10/12:16:09 Page 398 398 / 16 STARS WITH SPECIAL CHARACTERISTICS 16.1 VARIABLE STARS by Douglas S. Hall All types of variables are collected in the General Catalogue of Variable Stars [1]. Except for the eclipsing variables, all are considered intrinsic variables, with the physical mechanism responsible for the variability being of four main classes. The approximate numbers of the principal types, as of 1990, are given in the following: Abbreviation Description Number Pulsating (periodic, multiperiodic, quasiperiodic, or nonperiodic) DCEP/CEP Classical Cepheids + those of uncertain type 638 CW W Virginis stars + BL Herculis stars 172 RR RR Lyrae stars 6180 DSCT δ Scuti stars (some called dwarf Cepheids) 100 SXPHE SX Phe variables, pop. II δ Sct variables 15 BCEP β Cephei stars = β Canis Majoris stars 89 ZZ ZZ Ceti variables 28 RV RV Tauri stars 120 SR Semiregular (sometimes called LPV) variables 3377 L Slow irregular (sometimes called LPV) variables 2389 M Mira stars (sometimes called LPV) 5827 RCB R Coronae Borealis stars 37 Rotating (periodic or quasiperiodic) ELL Ellipsoidal variables 45 ACV α2 Canum Venaticorum variables 163 SXARI SX Ari variables 15 PSR Optically variable pulsars 2 BY BY Draconis variables 34 RS RS Canum Venaticorum binaries 67 FKCOM FK Comae Berenices stars 4 INT Orion variables of the T Tauri type 59 Sp.-V/AQuan/1999/10/12:16:09 Page 399 16.2 CEPHEID AND CEPHEID-LIKE VARIABLES / 399 Eruptive (all nonperiodic) IN Orion variables, including T Tauri stars and RW Aurigae stars 898 FU FU Orionis variables 3 GCAS γ Cassiopeiae variables 108 RCB R Coronae Borealis variables 37 UV UV Ceti variables or flare stars 746 SDOR S Doradus variables or P Cygni stars 15 Explosive or Cataclysmic (quasiperiodic or nonperiodic) N Novae 61 NL Novalike variables 30 NR Recurrent novae 8 SN Supernovae 7 UG U Geminorum variables or dwarf novae 182 ZAND Symbiotic variables of the Z Andromedae type 46 Eclipsing (periodic) all types 5074 16.2 CEPHEID AND CEPHEID-LIKE VARIABLES Descriptions of Cepheid families are given below [2–13]: Period IAU designation Name Population (days) DCEP Classical Cepheids I 1.5–60 CW W Vir + BL Her stars II 1–50 RR RR Lyrae stars II 0.4–1 DSCT δ Scuti I 0.04–0.2 BCEP β Cephei stars I 0.15–0.25 Cepheid mean characteristics as a function of period P are given below. The period is that of the fundamental mode. In the K band MK =−2.97 log P − 1.08. The Cepheid ratio of radial velocity amplitude to V -light amplitude is 50 ± 5kms−1 mag.−1. Sp.-V/AQuan/1999/10/12:16:09 Page 400 400 / 16 STARS WITH SPECIAL CHARACTERISTICS a log PMV B − V log L/L log R/R log Teff log M/M log gQ Classical Cepheids 0.4 −2.4 0.49 2.81 1.41 3.76 0.54 2.2 0.036 0.6 −2.9 0.57 3.05 1.55 3.75 0.61 1.9 0.037 0.8 −3.5 0.66 3.30 1.70 3.74 0.68 1.7 0.039 1.0 −4.1 0.75 3.55 1.85 3.72 0.75 1.5 0.040 1.2 −4.7 0.84 3.80 2.00 3.71 0.82 1.3 0.041 1.4 −5.3 0.93 4.06 2.15 3.70 0.89 1.0 0.042 1.6 −5.8 1.01 4.32 2.29 3.70 0.97 0.8 0.044 1.8 −6.4 1.10 4.58 2.44 3.69 1.04 0.6 0.045 δ Sct/Dwarf Cepheidsb −1.4 +2.7 0.20 0.90 0.07 3.91 0.21 4.5 0.039 −1.0 +1.7 0.25 1.22 0.37 3.88 0.25 3.9 0.037 −0.7 +0.8 0.29 1.58 0.59 3.86 0.31 3.6 0.037 Population II Cepheids 0.1 −0.1 0.30 1.95 0.86 3.82 −0.22 2.5 0.049 0.5 −0.9 0.44 2.27 1.08 3.79 −0.22 2.1 0.059 1.0 −1.8 0.60 2.63 1.34 3.75 −0.22 1.5 0.076 1.3 −2.4 0.70 2.87 1.52 3.72 −0.22 1.2 0.080 RR Lyrae starsc −0.5 0.7 0.20 1.47 0.54 3.86 −0.26 3.1 0.036 −0.3 0.7 0.25 1.57 0.67 3.82 −0.26 2.8 0.037 −0.1 0.7 0.38 1.59 0.76 3.78 −0.26 2.7 0.043 β Cephei stars −1.0 −2.5 −0.23 3.99 0.84 4.34 1.02 3.8 0.020 −0.8 −3.1 −0.25 4.33 0.93 4.38 1.15 3.7 0.030 −0.6 −3.8 −0.27 4.69 1.03 4.42 1.22 3.6 0.037 Notes . a Q ≡ P(ρ/ρ)0 5 is the pulsation constant expressed in days. bMany of these stars show higher-order and/or nonradial modes as well. c MV depends on metallicity: MV = 0.20[Fe/H] + 1.0. 16.3 VARIABLE WHITE DWARF TABLES by Paul A. Bradley Tables 16.1, 16.2, and 16.3 give data for the DAV, DBV, and DOV variable white dwarfs, respectively. Sp.-V/AQuan/1999/10/12:16:09 Page 401 Table 16.1. Names, positions, and magnitudes of the ZZ Ceti (DAV) stars. Variable star Teff VBAmp. Periods WD No. Name name α (2000.0) δ (2000.0) (103 K) (mag.) (mag.) (mag.) (seconds) 0104 −464 BPM 30551 [1, 2] AX Phe 01 06 56 −46 10.2 11.3 [46, 47] 15.26 15.43 0.22 823 + others 0133 −116 R 548 [3–5] ZZ Cet 01 36 10 −11 20.7 12.0 [46–50] 14.16 14.33 0.012 213, 274 0341 −459 BPM 31594 [6–8] VY Hor 03 43 25 −45 48.7 11.5 [46, 47] 15.03 15.24 0.28 402, 618, C, Ha 0416 +272 HL Tau 76 [9–11] V411 Tau 04 18 59 +27 18.4 11.4 [46, 47] 15.20 15.40 0.28 393, 625, 746, C, H 0417 +361 G 38-29 [12] V468 Per 04 20 18 +36 16.6 11.2 [46, 47] 15.59 15.79 0.22 ∼ 1000, C, H 0455 +553 G 191-16 [13, 14] BR Cam 04 59 28 +55 25.3 11.4 [46, 47] 15.98 16.1 0.3 510, 600, 710893, C, H 0507 +0435 HS0507+0434B [15] — 05 10 13 +04 38.6 11.8 15.36 15.6 0.2 355, 445, 560, CH 0517 +307 GD 66 [16, 17] V361 Aur 05 20 38 +30 48.5 12.0 [46, 49, 50] 15.56 15.78 0.02 197, 272, 302, 819, C, H 0837 +403 KUV 08368+4026 [18] — 08 40 08 +40 15.1 — 15.55 15.77 0.03 495, 618 0858 +363 GD 99 [19] VW Lyn 09 01 49 +36 07.2 11.8 [46–49, 51] 14.55 14.74 0.07 350, 481, 592 0921 +354 G117-B15A [20–22] RY LMi 09 24 17 +35 16.9 11.6 [46–51] 15.50 15.72 0.05 215, 271, 304, C, H 1137 +422 KUV 11370+4222 [18] — 11 39 41 +42 05.3 — 16.56 16.78 0.006 257 + others 1159 +803 G255-2 [23] BT Cam 12 01 48 +80 05.0 11.4 [46, 47] 16.04 — 0.04 685, 830 + others 16.3 V 1236 −495 BPM 37093 [24] V886 Cen 12 38 48 −49 49.0 11.7 [46, 48, 50, 51] 13.96 14.14 0.004 ∼ 600 1307 +354 GD 154 [25, 26] BG CVn 13 09 58 +35 09.5 11.2 [46, 48–51] 15.33 15.51 0.10 403, 1089, 1186, C, H 1350 +656 G 238-53 [27] DU Dra 13 52 12 +65 24.9 11.9 [46, 49] 15.51 15.7 0.02 ∼ 206 1401 −1454 EC 14012−1446 [28] IU Vir 14 03 57 −15 01.1 — 15.67 15.50 0.30 610, 724 + others ARIABLE 1422 +095 GD 165 [29–31] CX Boo 14 24 40 +09 17.3 12.0 [46, 49] 14.32 14.46 0.10 114, 120 192, 250, C 1425 −811 L 19-2 [32–34] MY Aps 14 32 18 −81 20.1 12.1 [46, 48–51] 13.75 14.00 0.03 113, 118, 143, 192, 350 1559 +369 R 808 [19] TY CrB 16 01 21 +36 47.0 11.2 [46, 48] 14.36 14.53 0.15 833, complex, C, H 1647 +591 G 226-29 [35, 36] DN Dra 16 48 26 +59 03.5 12.5 [46–51] 12.24 12.40 0.006 109 1714 −547 BPM 24754 [37] — 17 18 54 −54 47.1 12.9 15.60 15.87 0.07 ∼ 1100 W 1855 +338 G 207-9 [38] V470 Lyr 18 57 30 +33 57.2 12.0 [46–48, 51] 14.62 14.81 0.06 259, 292, 557, 739, C HITE 1935 +276 G 185-32 [13] PY Vul 19 37 13 +27 43.3 12.1 [46–48, 50, 51] 12.97 13.15 0.02 141, 215, C, H 1950 +250 GD 385 [7, 39] PT Vul 19 52 28 +25 09.3 11.7 [46, 47] 15.12 15.32 0.05 256, C 2303 +242 PG 2303+242 [40, 41] KR Peg 23 06 16 +24 32.0 11.5 [46, 47] 15.50 15.58b 0.2 394, 483, 540, 611, 936, C, H D 2326 +049 G 29-38 [12, 42–44] ZZ Psc 23 28 49 +05 15.0 11.8 [46–50] 13.03 13.17 0.27 284, 615, 820, C, H WARF 2349 −244 EC 23487−2424 [45] HW Aqr 23 51 22 −24 08.2 — 15.33 15.52 0.24 ∼ 800–1000, complex Notes T aC means combination of frequencies and H means harmonics.
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  • Pos(ICRC2019)832 † ∗ [email protected] Speaker
    Probing Particle Diffusion around Two Nearby Pulsars with TeV Gamma-Ray Observations from HAWC PoS(ICRC2019)832 Hao Zhou∗ Los Alamos National Laboratory E-mail: [email protected] for the HAWC Collaborationy Nearby cosmic-ray accelerators, especially pulsar wind nebulae, are possible origins of the local multi-GeV positron excess. Pulsar Geminga and B0656+14, less than 300 pc from the Earth, have been postulated as the main sources of the positron excess. With one and half years of data, the HAWC gamma-ray observatory discovered very extended TeV gamma-ray structures produced from high-energy electrons and positrons around these two nearby middle-aged pulsars. Morphology studies suggest that the diffusion in the vicinity of these two pulsars is 100 times slower than the average in our Galaxy. This result provides important constraints on the origin of positron excess, but raises questions like why diffusion is so slow at high energies near these pulsars. With more than twice of data from the previous results, we now explore the possibility of energy-dependent diffusion at these sources. 36th International Cosmic Ray Conference -ICRC2019- July 24th - August 1st, 2019 Madison, WI, U.S.A. ∗Speaker. yFor a complete author list and acknowledgemets, see PoS(ICRC2019)1177 and http://www.hawc- observatory.org/collaboration/icrc2019.php c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/ Probing Particle Diffusion with HAWC Hao Zhou 1. Introduction Pulsar wind nebulae are known as efficient particle accelerators of electrons and positrons.
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