Variable Heating and Flaring of Three Redback Millisecond Pulsar Companions

Cho, Patricia B.; Halpern, J. P.; Bogdanov, Slavko

doi:10.3847/1538-4357/aade92

Cited by 43 publications

(58 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Individual X-ray flaring events are not uncommon in redback and black widow systems, e.g., PSRJ1048+2339 (Cho et al 2018;Yap et al 2019), 3FGLJ0838.8−2829 (Halpern et al 2017), and PSRJ1311−3430 (Romani 2012;Romani et al 2015;An et al 2017), but this paper is the first to show evidence for a system with a fully flare-dominated accretion mode. Perhaps the closest comparison is the few flare-dominated epochs of PSRJ1023+0038 in its subluminous disk state (Tendulkar et al 2014;Li et al 2014;Papitto et al 2019), though these have typically been short-lived, and make up only a small fraction of the observed modes in the current accretion state of PSRJ1023 +0038.…”

Section: Discussionmentioning

confidence: 74%

The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar

Strader²,

Miller-Jones

et al. 2020

ApJ

View full text Add to dashboard Cite

We report new simultaneous X-ray and radio continuum observations of 3FGLJ0427.9−6704, a candidate member of the enigmatic class of transitional millisecond pulsars. These XMM-Newton and Australia Telescope Compact Array observations of this nearly edge-on, eclipsing low-mass X-ray binary were taken in the subluminous disk state at an X-ray luminosity of~d 10 2.3 kpc 33 2 () erg s −1. Unlike the few well-studied transitional millisecond pulsars, which spend most of their disk state in a characteristic high or low accretion mode with occasional flares, 3FGLJ0427.9−6704 stayed in the flare mode for the entire X-ray observation of ∼20 hr, with the brightest flares reaching ∼2×10 34 erg s −1. The source continuously exhibited flaring activity on timescales of ∼10-100 s in both the X-ray and optical/ultraviolet (UV). No measurable time delay between the X-ray and optical/UV flares is observed, but the optical/UV flares last longer, and the relative amplitudes of the X-ray and optical/UV flares show a large scatter. The X-ray spectrum can be well-fit with a partially absorbed power law (Γ∼1.4-1.5), perhaps due to the edge-on viewing angle. Modestly variable radio continuum emission is present at all epochs, and is not eclipsed by the secondary, consistent with the presence of a steady radio outflow or jet. The simultaneous radio/X-ray luminosity ratio of 3FGLJ0427.9−6704 is higher than any known transitional millisecond pulsars and comparable to that of stellar-mass black holes of the same X-ray luminosity, providing additional evidence that some neutron stars can be as radio-loud as black holes.

show abstract

Section: Discussionmentioning

confidence: 74%

The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar

Strader²,

Miller-Jones

et al. 2020

ApJ

View full text Add to dashboard Cite

show abstract

“…These observations support the idea of the presence of magnetic fields throughout the material ablated from the companion, and also suggest that particular magnetic structures can persist in the system for many months. It may be that such variations in the DM profiles are linked to variations in an intrabinary shock, or activity in the companion such as those suggested by Cho et al (2018) and Yap et al (2019).…”

Section: L-bandmentioning

confidence: 98%

Long-term variability of a black widow’s eclipses – A decade of PSR J2051$-$0827

Polzin

Breton

Stappers

et al. 2019

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

In this paper we report on ∼ 10 years of observations of PSR J2051−0827, at radio frequencies in the range 110-4032 MHz. We investigate the eclipse phenomena of this black widow pulsar using model fits of increased dispersion and scattering of the pulsed radio emission as it traverses the eclipse medium. These model fits reveal variability in dispersion features on timescales as short as the orbital period, and previously unknown trends on timescales of months-years. No clear patterns are found between the low-frequency eclipse widths, orbital period variations and trends in the intra-binary material density. Using polarisation calibrated observations we present the first available limits on the strength of magnetic fields within the eclipse region of this system; the average line of sight field is constrained to be 10 −4 G B | | 10 2 G, while for the case of a field directed near-perpendicular to the line of sight we find B ⊥ 0.3 G. Depolarisation of the linearly polarised pulses during the eclipse is detected and attributed to rapid rotation measure fluctuations of σ RM 100 rad m −2 along, or across, the line of sights averaged over during a sub-integration. The results are considered in the context of eclipse mechanisms, and we find scattering and/or cyclotron absorption provide the most promising explanation, while dispersion smearing is conclusively ruled out. Finally, we estimate the mass loss rate from the companion to be M C ∼ 10 −12 M yr −1 , suggesting that the companion will not be fully evaporated on any reasonable timescale.

show abstract

“…For the orbital fit, P and T 0 were fixed to the pulsar ephemerides (Cho et al 2018), leaving only K 2 and γ to be fit. We find K 2 = 358(10) km s −1 and γ = −4(7) km s −1 .…”

Section: Psr J1622-0315mentioning

confidence: 99%

Optical Spectroscopy and Demographics of Redback Millisecond Pulsar Binaries

Strader¹,

Swihart²,

Chomiuk³

et al. 2019

ApJ

117

138

View full text Add to dashboard Cite

We present the first optical spectroscopy of five confirmed (or strong candidate) redback millisecond pulsar binaries, obtaining complete radial velocity curves for each companion star. The properties of these millisecond pulsar binaries with low-mass, hydrogen-rich companions are discussed in the context of the 14 confirmed and 10 candidate field redbacks. We find that the neutron stars in redbacks have a median mass of 1.78 ± 0.09M with a dispersion of σ = 0.21 ± 0.09. Neutron stars with masses in excess of 2M are consistent with, but not firmly demanded by, current observations. Redback companions have median masses of 0.36 ± 0.04M with a scatter of σ = 0.15 ± 0.04M , and a tail possibly extending up to 0.7-0.9M . Candidate redbacks tend to have higher companion masses than confirmed redbacks, suggesting a possible selection bias against the detection of radio pulsations in these more massive candidate systems. The distribution of companion masses between redbacks and the less massive black widows continues to be strongly bimodal, which is an important constraint on evolutionary models for these systems. Among redbacks, the median efficiency of converting the pulsar spindown energy to γ-ray luminosity is ∼ 10%.

show abstract

Variable Heating and Flaring of Three Redback Millisecond Pulsar Companions

Cited by 43 publications

References 37 publications

The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar

The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar

Long-term variability of a black widow’s eclipses – A decade of PSR J2051$-$0827

Optical Spectroscopy and Demographics of Redback Millisecond Pulsar Binaries

Contact Info

Product

Resources

About