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We present XMM-Newton observations and spectral fitting of two highly redshift, [OIII]-luminous, narrow-line radio galaxies, B3 0731+438 and 3C 257. Their X-ray continua are well fitted by a partial covering model with intrinsically unabsorbed and absorbed powerlaw components. The spectral models indicate that both objects harbour highly obscured nuclei, with N_H ~ 0.5 - 2 x 10^23 cm^-2. Correcting for this absorption we find large intrinsic luminosities in the range L_X ~ 0.2 - 1 x 10^45 erg/s. Thus, both sources are type-2 quasars.
We report on infrared imaging observations of the z=2.429 radio galaxy B3 0731+438 with the Subaru telescope. The images were taken with the K'-band filter and the 2.25 um narrow-band filter to examine the structure and properties of the Ha+[N II] 6548,6583 emission-line components. The Ha+[N II] emission-line image shows biconical lobes with an extent of 40 kpc, which are aligned with the radio axis. The rest-frame equivalent widths of the emission lines at these cones are as large as 1100 AA, and can be well explained by a gas-cloud model photoionized by power-law continuum radiation. The isotropic ionizing photon luminosity necessary to ionize the hydrogen gas in these cones amounts to 1e57(photons/s), which is larger than that in the majority of radio-loud QSOs. From these results, we propose that the Ha alignment effect in this object is produced by biconical gas clouds, which are swept up by the passage of radio jets, and are ionized by strong UV radiation from a hidden AGN. The continuum image consists of two components, a stellar-like point source and an extended diffuse galaxy. These are supposed to be a type-2 AGN and its host galaxy. The SED is fitted by a combination of
We present upgraded Giant Metrewave Radio Telescope (uGMRT) observations of 0731+438, an \mbox{FR II} radio galaxy at a redshift of 2.429 with two lobes separated by 82 kpc. A blueshifted, faint and broad \mbox{H{\sc i}} 21 cm absorption line with velocity full width at half maximum (FWHM) $\sim 600\,\rm km\,s^{-1}$ is detected against the southern radio lobe that is 47 kpc from radio core, indicating a neutral hydrogen outflow associated with jet-gas interaction beyond the host galaxy. The outflow has a mass outflow rate of $\sim\,0.4T_{\rm s}Ω\rm\, M_\odot\,{\rm yr}^{-1}$, which could increase to $\sim\,4.0T_{\rm s}Ω\rm\,M_\odot\,{\rm yr}^{-1}$, corresponding to an energy outflow rate of $2.4T_{\rm s}Ω\times10^{40}$ -- $1.5T_{\rm s}Ω\times10^{41}\,\rm erg\,s^{-1}$, where $T_{\rm s}$ is the spin temperature and $Ω$ is the solid angle of the outflow. Previous optical observations identified an extended emission line region aligned with the radio axis, ionized by the central Active Galactic Nucleus (AGN). Within this region, a warm and ionized outflow with a mass outflow rate of $\sim\,50\rm\, M_\odot\,{\rm yr}^{-1}$ and an energy outflow rate of $\sim1.7\times10^{43}\,\rm erg\,s^{-
We present new infrared data from a survey for embedded protostellar jets in the Orion A cloud. This survey makes use of the S(1) v = 1-0 line of molecular hydrogen at lambda = 2.12 mum to search for infrared jets deep inside the cloud and thus hidden from view at optical wavelengths. We present data on the three flows associated with the Herbig-Haro objects HH 43/38 & HH 64, HH 65, and the L1641-N giant flow. HH 43, HH 38 and HH 64 are part of one H_2 flow extending over at least 1.4 pc. We identify a deeply embedded 1.3 mm and IRAS source (HH 43 MMS1 = IRAS 05355-0709C) as the likely driving source, while the infrared source previously assumed to drive HH 43/38 (HH 43-IRS1 = IRAS 05357-0710) is seen to drive a smaller jet. The morphology of HH 43-IRS1 suggests that it is a star+disk system seen close to edge-on. We identify another large H_2 flow apparently comprising the L1641-S3 CO outflow and the redshifted lobe of the L1641-S CO outflow containing HH 65. This flow extends over at least 2.6 pc and appears strongly curved. It is driven by L1641-S3 IRS, a deeply embedded 1.3 mm and IRAS source (L1641-S3 MMS1 = IRAS 05375-0731). Finally, we have found some additional large H_
We present optical and near-infrared adaptive optics (AO) imaging and spectroscopy of 13 ultracool (>M6) companions to late-type stars (K7-M4.5), most of which have recently been identified as candidate members of nearby young moving groups (YMGs; 8-120 Myr) in the literature. The inferred masses of the companions (~10-100 Mjup) are highly sensitive to the ages of the primary stars so we critically examine the kinematic and spectroscopic properties of each system to distinguish bona fide YMG members from old field interlopers. 2MASS J02155892-0929121 C is a new M7 substellar companion (40-60 Mjup) with clear spectroscopic signs of low gravity and hence youth. The primary, possibly a member of the ~40 Myr Tuc-Hor moving group, is visually resolved into three components, making it a young low-mass quadruple system in a compact (<100 AU) configuration. In addition, Li 1 $λ$6708 absorption in the intermediate-gravity M7.5 companion 2MASS J15594729+4403595 B provides unambiguous evidence that it is young (<200 Myr) and resides below the hydrogen burning limit. Three new close-separation (<1") companions (2MASS J06475229-2523304 B, PYC J11519+0731 B, and GJ 4378 Ab) orbit sta
The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system。 Its unusual chemistry suggests that planet-cooling dust and debris, rather than sulfur inside the asteroid, may have delivered the deadliest blow
Rice University chemists have found a new way to make neodymium, a rare-earth metal, interact with oxygen。 Using a specially designed molecular structure described as a “basket,” the team positioned the atoms so they could form a bond once thought unlikely。 The breakthrough produced highly reactive compounds that could eventually give chemists alte
A disputed exam, an unreliable detector, and one very late Apple Pages file
A new particle detector called PLATON could replace millions of tiny detector components with a single block of light-producing material。 Using a light-field camera, highly sensitive photon sensors, and AI, it reconstructs particle paths in fast, detailed 3D。 Simulations suggest it could match or surpass today’s best detectors while being far easie
Plus, a new policy for the AI protocol ensures features aren't removed suddenly
Scientists are testing two promising ways to destroy PFAS, the stubborn “forever chemicals” that can accumulate in water and resist normal treatment。 One method uses collapsing vapor bubbles to generate extreme heat and reactive molecules, while the other uses cold plasma and rising gas bubbles to pull PFAS to the surface and break them apart
The Backrooms began as a single eerie image of empty yellow rooms, but internet users transformed it into a vast fictional world that feels disturbingly real。 Through videos, games, maps, survival guides and social media stories, audiences do more than watch the horror unfold。 They help build and explore it
Scientists have uncovered new evidence that Venus may still be tearing itself apart from within。 Advanced 3D simulations indicate that some of the planet's giant rift valleys formed relatively recently and could still be expanding。 The results suggest Venus has a far more active interior than researchers once believed, challenging the long-held vie
Wavelength and intensity in the infrared are translated into colors in the visible
NASA’s Swift Observatory observed a supermassive black hole ripping apart a star more than 30,000 light-years from the center of a distant galaxy。 The extraordinary flare briefly outshone its entire host galaxy in ultraviolet light and revealed a black hole about a million times the Sun’s mass
A new review highlights exciting progress in atomically thin quantum materials where light and magnetism work together in ways never before possible。 In these materials, light-generated excitons can interact directly with magnetic behavior, creating opportunities to control magnetic states using light alone。 Scientists believe this could pave the w
A distant Sun-like star appears to have devoured one of its planets, leaving behind a surprising chemical fingerprint。 Researchers found an unusually high concentration of lithium, a strong sign that planetary material was mixed into the star。 Careful comparisons with dozens of similar stars confirmed the signal is highly unusual, and scientists th