The near-infrared detection of PSR B0540-69 and its nebula

Abstract

The ~1700 year old PSR B0540-69 in the LMC is considered the twin of the Crab pulsar because of its similar spin parameters, magnetic field, and energetics. Its optical spectrum is fit by a power-law, ascribed to synchrotron radiation, like for the young Crab and Vela pulsars. nIR observations, never performed for PSR B0540-69, are crucial to determine whether the optical power-law spectrum extends to longer wavelengths or a new break occurs, like it happens for both the Crab and Vela pulsars in the mIR, hinting at an even more complex particle energy and density distribution in the pulsar magnetosphere. We observed PSR B0540-69 in the J, H, and Ks bands with the VLT to detect it, for the first time, in the nIR and characterise its optical-to-nIR spectrum. To disentangle the pulsar emission from that of its pulsar wind nebula (PWN), we obtained high-spatial resolution adaptive optics images with NACO. We could clearly identify PSR B0540-69 in our J, H, and Ks-band images and measure its flux (J=20.14, H=19.33, Ks=18.55, with an overall error of +/- 0.1 magnitudes in each band). The joint fit to the available optical and nIR photometry with a power-law spectrum gives a spectral index alpha=0.70 +/-0.04. The comparison between our NACO images and HST optical ones does not reveal any apparent difference in the PWN morphology as a function of wavelength. The PWN optical-to-nIR spectrum is also fit by a single power-law, with spectral index alpha=0.56+/- 0.03, slightly flatter than the pulsar's. Using NACO at the VLT, we obtained the first detection of PSR B0540-69 and its PWN in the nIR. Due to the small angular scale of the PWN (~4") only the spatial resolution of the JWST will make it possible to extend the study of the pulsar and PWN spectrum towards the mid-IR.

11 pages, 10 figures, Accepted for publication on Astronomy and Astrophysics

References in corpus (12)

• The Second-Generation Guide Star Catalog: Description and Properties
• The Infrared Detection of the Pulsar Wind Nebula in the Galactic Supernova Remnant 3C 58
• Ejecta, Dust, and Synchrotron Radiation in B0540-69.3: A More Crab-Like Remnant than the Crab
• Optical and infrared observations of the Crab Pulsar and its nearby knot
• UV emission from young and middle-aged pulsars: Connecting X-rays with the optical
• Optical identification of the 3C 58 pulsar wind nebula
• VLT/NACO observations of the High-Magnetic field radio pulsar PSR J1119-6127
• High Energy Emission from Rotation-Powered Pulsars: Outer-gap vs. Slot-gap Models
• HST multi-epoch imaging of the PSR B0540-69 system unveils a highly dynamic synchrotron nebula
• A likely optical counterpart of the G292.0+1.8 pulsar wind nebula
• The G292.0+1.8 pulsar wind nebula in the mid-infrared
• Optical timing studies of isolated neutron stars: Current Status

Cited by in corpus (24)

• The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Nature of the Galactic centre NIR-excess sources. I. What can we learn from the continuum observations of the DSO/G2 source?
• Synchro-curvature modelling of the multi-frequency non-thermal emission of pulsars
• Discovery of extended infrared emission around the neutron star RX J0806.4-4123
• Utilizing cosmic-ray positron and electron observations to probe the averaged properties of Milky Way pulsars
• Is there room for highly magnetized pulsar wind nebulae among those non-detected at TeV?
• Atacama Compact Array Observations of the Pulsar-Wind Nebula of SNR 0540-69.3
• The PSR J1124-5916 wind nebula in the near-infrared
• The first ultraviolet detection of the Large Magellanic Cloud pulsar PSR B0540-69 and its multi-wavelength properties
• The nature of the infrared counterpart and of the optical nebula associated with the Central Compact Object in Vela Jr.\
• Optical Observations of PSR J0205+6449 - the next optical pulsar?
• PSR B0656+14: the unified outlook from the infrared to X-rays
• The optical and near-infrared spectrum of the Crab pulsar with X-shooter
• Near-infrared observations of PSR J1357-6429
• VLT polarimetry observations of PSR B0656+14
• Kinematics, structure and abundances of supernova remnant 0540-69.3
• Multi-wavelength observations of Isolated Neutron Stars
• Spatial Variations and Breaks in the Optical-NIR spectra of the Pulsar and PWN in SNR 0540-69.3
• The Nature and Likely Redshift of GLEAM J0917-0012
• Possible counterpart signal of the Fermi bubbles at the cosmic-ray positrons
• Analysis of the possible detection of the pulsar wind nebulae of PSR J1208-6238, J1341-6220, J1838-0537 and J1844-0346
• Large Binocular Telescope observations of PSR J2043+2740
• Enhanced Doppler Beaming for Dust-Enshrouded Objects and Pulsars in the Galactic Center
• Search of nearby resolved neutron stars among optical sources