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Spider pulsars are neutron stars that have a companion star in a close orbit. The companion star sheds material to the neutron star, spinning it up to millisecond rotation periods, while the orbit shortens to hours. The companion is eventually ablated and destroyed by the pulsar wind and radiation1,2. Spider pulsars are key for studying the evolutionary link between accreting X-ray pulsars and isolated millisecond pulsars, pulsar irradiation effects and the birth of massive neutron stars3–6. Black widow pulsars in extremely compact orbits (as short as 62 minutes7) have companions with masses much smaller than 0.1 M⊙. They may have evolved from redback pulsars with companion masses of about 0.1–0.4 M⊙and orbital periods of less than 1 day8. If this is true, then there should be a population of millisecond pulsars with moderate-mass companions and very short orbital periods9, but, hitherto, no such system was known. Here we report radio observations of the binary millisecond pulsar PSR J1953+1844 (M71E) that show it to have an orbital period of 53.3 minutes and a companion with a mass of around 0.07 M⊙. It is a faint X-ray source and located 2.5 arcminutes from the centre of the globular cluster M71.

Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1–3. Recent observations of a Galactic FRB4–8suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (au; Earth–Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10–12show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.

Fast radio bursts (FRBs) are millisecond-duration radio transients1,2of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres3–5or relativistic shocks far from the central energy source6–8. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters9,10or variable polarization angles in some other apparently one-off events11,12. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1–3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4–13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18–21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB–SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

Context. The spiral structure of our Milky Way Galaxy is not yet known. HII regions and giant molecular clouds are the most prominent spiral tracers. Models with 2-4 arms have been proposed to outline the structure of our Galaxy.

Aims. Our purpose is to place firm observational constraints on the three most widely used theoretical models for the spatial configuration of the large-scale interstellar magnetic field in the Galactic disk, namely, the ring, the axisymmetric, and the bisymmetric field models.

Context. Evidence for a spectral flattening of the supernova remnant (SNR) HB3 (G132.7+1.3) was recently claimed in the literature based on previously published total flux density data, and the flattening was further interpreted as the discovery of thermal bremsstrahlung emission in the shell of HB3.

Context. S147 is a large faint shell-type supernova remnant (SNR) known for its remarkable spectral break at cm-wavelength, which is an important physical property to characterize SNR evolution. However, the spectral break is based on radio observations with limited precision.

Wideband signals from a radio telescope have to be channelized for spectral observations or for dedispersion for pulsar observations. A polyphase filter bank is designed based on the improved weighted overlap-add (IWOLA) algorithm to achieve channelization. The IWOLA algorithm involves applying an equivalent Hilbert transform to the normal WOLA filter bank by shifting the center frequency of every sub-band by a half of the frequency bin, so that the IWOLA filter bank provides Kindependently output complex subbands instead of the usual K+ 1 sub-bands, reducing the subsequent processing units by one set. Performance of the proposed IWOLA filter bank is analyzed by means of MATLAB simulations. We show how the IWOLA filter bank can be used for a two-stage, high-resolution spectrometer, with a much reduced consumption of FPGA on-chip block RAM.

Context.G156.2+5.7 is a large supernova remnant (SNR) first discovered in the ROSAT X-ray survey due to its exceptional high X-ray brightness. Subsequently detailed X-ray, optical and Hαstudies of this SNR were made, but radio observations are rare because of its low surface brightness and large size.

Context.Short time-scale radio variations of compact extragalactic radio sources, known as IntraDay Variability (IDV), can be explained in at least some sources by a source-extrinsic effect, in which the variations are interpreted as scintillation of radio waves caused by the turbulent interstellar medium of the Milky Way. One of the most convincing observational arguments in favour of propagation-induced variability is the so-called “annual modulation” of the characteristic variability time-scale, which is due to the orbital motion of the Earth. So far there are only two sources known which show such a well-defined seasonal cycle, a few more sources with fewer data can be regarded as possible candidates for this effect. However, source-intrinsic effects, such as structural variations, can also cause the observed changes of the variability time-scale. Data for the new, recently discovered, and highly variable IDV source J 1128+5925 are presented.

The region in which pulsars radiate is very important to constrain pulsar emission mechanisms. A three-dimensional (3D) method to calculate emission heights is developed in this paper. As an example, radiation regions for different components at different frequencies have been calculated for PSR B2111+46. Emission components at seven frequencies are fitted with Gaussian components, then the radiation heights for emission components are calculated. We found that different emission components, even if at the same radio frequency, are radiated from different heights. This is probably a common phenomena and challenges any emission mechanisms. The inverse Compton scattering emission model for pulsar radio emission can explain these results well.

Aims.Magnetic fields exist on all scales in our Galaxy. There is a controversy about whether the magnetic fields in molecular clouds are preserved from the permeated magnetic fields in the interstellar medium (ISM) during cloud formation. We investigate this controversy using available data in the light of the newly revealed magnetic field structure of the Galactic disk obtained from pulsar rotation measures (RMs).

Aims.Polarization measurements of the Galactic plane at λ6 cm probe the interstellar medium (ISM) to larger distances compared to measurements at longer wavelengths, enabling us to investigate properties of the Galactic magnetic fields and electron density.

Context.The relationship between the emission-line equivalent width and the continuum luminosity, called the Baldwin effect, is important for studies of the physics of the broad-line region of AGNs. Some recent studies have revealed the non-constant slope of the intrinsic Baldwin effect for several Seyfert 1 galaxies.

Radio continuum and polarization observations of the entire Cygnus Loop at λ6 cm wavelength were made with the Urumqi 25 m telescope. The λ6 cm map is analysed together with recently published maps from the Effelsberg 100 m telescope at λ21 cm and λ11 cm. The integrated flux density of the Cygnus Loop at λ6 cm is 90 ±9 Jy, which implies a spectral index of $\alpha=-0.40$±0.06. This rules out any global spectral steepening up to λ6 cm. However, small spectral index variations in some regions of the source are possible, but there are no indications for any spectral curvature. The linear polarization data at λ6 cm show percentage polarizations up to 35% in some areas of the Cygnus Loop, exceeding those observed at λ11 cm. The Rotation Measure is around -21 rad m-2in the southern area, which agrees with previous observations. However, the distribution of Rotation Measures is rather complex in the northern part of the Cygnus Loop, where the λ21 cm emission is totally depolarized. Rotation Measures based on λ11 cm and λ6 cm data are significantly larger than in the southern part. The difference in the polarization characteristics between the northern and southern part supports previous ideas that the Cygnus Loop consists of two supernova remnants.

An empirical relation between the broad line region (BLR) size and optical continuum luminosity is often adopted to estimate the BLR size and then the black hole mass of AGNs. However, optical luminosity may not be a good indicator of photoionizing luminosity for extremely radio-loud AGNs because the jets usually contribute significantly to the optical continuum. Therefore, the black hole masses derived for blazar-type AGNs with this method are probably overestimated. Here we first derived a tight empirical relation between the BLR size and the Hβemission line luminosity, $R({\rm light-days})= 24.05(L_{{\rm H}_\beta}/10^{42}$ergs s$^{-1})^{0.68}$, from a sample of 34 AGNs with the BLR size estimated with the reverberation mapping technique. Then we applied this relation to estimate the black hole masses of some AGNs and found that for many extremely radio-loud AGNs the black hole masses obtained with the $R-L_{\rm H_\beta}$relation are systematically lower than those derived previously with the $R-L_{5100~{\rm \AA}}$relation, while for radio-quiet and slightly radio-loud AGNs the results obtained with these two methods are almost the same. The difference of black hole masses estimated with these two relations increases with the radio-loudness for extremely radio-loud AGNs, which is consistent with the fact that their equivalent widths of the H$_{\beta}$emission line become smaller at greater radio-loudness. If the small H$_{\beta}$equivalent widths of extremely radio-loud  AGNs are indeed caused by the beaming effect, we argue that the optical emission line luminosity may be a better tracer of ionizing luminosity for blazar-type AGNs and the black hole masses derived with the $R-L_{{\rm H}_\beta}$relation are probably more accurate.

The low-frequency profiles of some pulsars manifest temporal broadening due to scattering, usually accompanied by flat polarization position angle (PA) curves. Assuming that the scattering works on the 4 Stokes parameters in the same way, we have simulated the effect of scattering on polarization profiles and find that the scattering can indeed flatten the PA curves. Since the higher-frequency profiles suffer less from scattering, they are convolved with scattering models to fit the observed low-frequency profiles. The calculated flat PA curves exactly reproduce the corresponding observations.

We estimated black hole masses for 9 Seyfert 1 and 13 Seyfert 2 galaxies in the Palomar and CfA bright Seyfert samples using the tight correlation between black hole mass and bulge velocity dispersion. Combining other 13 Seyfert 1s and 2 Seyfert 2s in these samples but with black hole masses measured recently by reverberation mapping and stellar/gas dynamics, we studied the correlations of black hole masses with radio-loudness and bulge luminosities for a sample of 37 Seyfert galaxies. We found that if radio-loudness is measured using the optical and radio luminosities of the nuclear components, the black hole masses of radio-loud Seyfert 1s tend to increase with the radio-loudness. The black hole masses of all Seyfert galaxies increase with the radio power, but Seyfert galaxies have larger radio powers than nearby galaxies with the same black hole masses. In addition, the correlation between black hole masses and bulge V-band luminosities for Seyfert galaxies is consistent with that found for quasars and normal galaxies. The combined sample of 37 Seyfert galaxies, 15 quasars and 30 normal galaxies suggests a possible universal nonlinear relation between black hole and bulge masses, ${M_{\rm BH} \propto M}_{\rm bulge}^{1.74 \pm 0.14}$, which is slightly steeper than that found recently by Laor ([CITE]) for a smaller sample. This nonlinear relation is supported by a larger sample including 65 Seyfert galaxies. The different ${M_{\rm BH}/ M}_{\rm bulge}$ratio for galaxies with different bulge luminosities or different black hole masses may be explained by this relation. These results are consistent with some theoretical implications and are important for understanding the nature of radio emissions and the formation and evolution of supermassive black holes and galaxies.

The shapes of pulse profiles, especially their variations with respect to observing frequencies, are very important to understand emission mechanisms of pulsars. However, no previous attempt has been made to interpret their complicated phenomenology. In this paper, we present theoretical simulations for the integrated pulse profiles and their frequency evolution within the framework of the inverse Compton scattering (ICS) model proposed by Qiao ([CITE]) and Qiao & Lin ([CITE]). Using the phase positions of the pulse components predicted by the "beam-frequency figure" of the ICS model, we present Gaussian fits to the multi-frequency pulse profiles for some pulsars. It is shown that the model can reproduce various types of the frequency evolution behaviors of pulse profiles observed.

We identified 97 strong pulsars from the NRAO VLA Sky Survey (NVSS) at 1.4 GHz north of Dec(J2000) -40°. The total flux density, linear polarization intensity and polarization angle (PA) of all pulsars are extracted from the NVSS catalog. The well-calibrated PA measurement of 5 pulsars can be used for absolute PA calibrations in other observations. Comparing the source positions with those in the pulsar catalog, we got the first measurement of the proper motion upper limit of PSR B0031-07, which is $\mu_{\alpha}\cos\delta = -102\pm74$mas yr-1and $\mu_{\delta} = -105\pm78$mas yr-1.

A novel epoxy containing rigid rods in the side chain (SR‐epoxy) was synthesized by bulk polymerization. The SR‐epoxy resins were characterized by Fourier transform infrared. The cured SR‐epoxies showed excellent mechanical properties and high thermal stabilities. Scanning electron microscopy (SEM) of the cured SR‐epoxy illustrated a fiber‐like morphology. The thermal properties, dynamic mechanical properties, compatibility, and morphology of the SR‐epoxies were extensively investigated in the study. SEM photographs showed that there were some fiber‐like structures in the system of the SR‐epoxy containing the rigid‐rod group 4,4′‐bis(6‐hydroxyhexoxy) biphenyl, which formed a self‐reinforcing composite. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4030–4036, 2006

This study prepared an interpenetrating polymer network of bismaleimide and polybutylene adipate-based polyurethane-crosslinked epoxy (BMI/PU-EP IPN) using the simultaneous bulk polymerization technique. Infrared spectra analysis was also performed to identify the polyurethane-crosslinked epoxy (PU-EP). Also investigated herein were the mechanical properties including tensile strength, fracture energy, and Izod impact strength of various bismaleimide content in PU-EP matrix. In addition, differential scanning calorimetry and thermogravimetric analyses of the BMI/PU-EP IPN were conducted as well. Analyses results demonstrate that the bismaleimide was dissolved primarily in the polyurethane domains of the epoxy matrix to form a compatible system, thereby increasing the mechanical strength of the BMI/PU-EP IPNs. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 529–536, 1998

In this work, we prepared the interpenetrating polymer networks of bismaleimide and polyether-type polyurethane(polyoxypropylene)–crosslinked epoxy (BMI/PU(PPG)–EP IPNs) by employing the simultaneous bulk polymerization technique. The polyurethane (PU)–crosslinked epoxy was identified via infrared (IR) spectra analysis. Also investigated herein were the mechanical properties, including tensile strength, Izod impact strength, and fracture energy (GIC) of the IPNs with various BMI contents in PU–crosslinked epoxy matrix. In addition, differential scanning calorimetry (DSC) analysis and the thermogravimetric analysis (TGA) were performed to examine the thermal properties of the BMI/PU(PPG)–EP IPNs. In addition, morphology and dynamic mechanical analysis (DMA) of the BMI/PU(PPG)–EP IPNs were also studied. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2635–2645, 1998

We present a systematic study of the circular polarization in pulsar integrated profiles, based on published polarization data. For core components, we find no significant correlation between the sense change of circular polarization and the sense of linear position‐angle variation. Circular polarization is not restricted to core components and, in some cases, reversals of circular polarization sense are observed across the conal emission. In conal double profiles, the sense of circular polarization is found to be correlated with the sense of position‐angle variation. Pulsars with a high degree of linear polarization often have one hand of circular polarization across the whole profile. For most pulsars, the sign of circular polarization is the same at 50‐cm and 20‐cm wavelengths, and the degree of polarization is similar, albeit with a wide scatter. However, at least two cases of frequency‐dependent sign reversals are known. This diverse behaviour may require more than one mechanism to generate circular polarization.

In this paper we argue that the PSR B 1849+00 and SNR G33.6+0.1 are possibly associated, because (1) there is only a small probability of chance superposition in this sky region; (2) although the estimates of the distance and the age of the two objects contain a high degree of uncertainty, they are not inconsistent; (3) the implied transverse velocity of the pulsar is also quite reasonable according to the measured distribution of pulsar velocities. The association could be verified by measuring the proper motion of PSR B 1849+00, which is estimated to be about 10 mas·yr-1.

• Human corneas were studied by means of electron microscopy after culture at 31 °C for two to 20 days in a medium containing 8% dextran T 500. Dextran T 500, a strong osmotic agent, was included in the culture medium to prevent excessive swelling of the cornea. In order to exclude the possibility that the observed effects were the result of osmotic changes during fixation, in each experiment, fixatives with different osmolalities were used (430, 574, 727, and 812 mOsm). After 8, 16, and 20 days of culture, vacuoles appeared that were filled with dextran; the cytoplasm was completely filled with these vacuoles. The vacuolization was not limited to the endothelium, but was also observed in stromal keratocytes and to a limited extent in the epithelium. It was concluded that the monolayer of endothelium was still intact after 20 days of culture in medium containing 8% dextran T 500, and, secondly, that the dextran might have been taken up by endocytosis. Whether or not the uptake of dextran has a long-term toxic effect on the corneal cells remains to be elucidated.

The effect of carbamate (urethane) groups on the curing reaction of an epoxy catalyzed by tertiary amine was studied by infrared (IR) and differential scanning calorimetry (DSC) analysis. It was found that the aromatic-connected carbamate (Ar-carbamate) accelerated the consumption rate of epoxy in the epoxy/tertiary amine/Ar-carbamate reaction system, where the tertiary amine and Ar-carbamate was found to form an active complex with stoichiometric ratio in the curing reaction. However, under the introduction of aliphatic-connected carbamate (Al-carbamate) into the reaction system, no complex formed with the tertiary amine during the reaction and therefore no acceleration in the reaction rate was observed.

The swelling equilibrium and diffusion kinetics in various solvents of the maleimide-terminated polyurethanes (UBMIs) and of the triol and tetraol-crosslinked polyurethanes (PU) were studied. The polymer volume fraction of the UBMIs at swelling equilibrium is much higher than that of the tetraol-crosslinked PU networks for the same type of polyol used in the PU. It was explained by the high functionality of the UBMIs produced in the network structure. Furthermore, the molecular weight between crosslinks (Mc) has been calculated from the swelling model and the results exhibit good agreement with the proposed network structure. The early time sorption kinetic data were obtained to investigate the diffusion mechanism of the solvent in the networks. The solubility, diffusion coefficients, and permeability of the solvent in UBMI networks were found to be lower than in the multiol-crosslinked PU networks. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 1747–1755, 1997

Mean pulse profiles and polarization parameters at 435, 660 or 1500 MHz obtained using the ATNF Parkes radio telescope are presented for 66 southern pulsars. About half of these pulsars were discovered in the Parkes southern pulsar survey and most have no previously published polarization parameters. Where possible, beam impact parameters and inclination angles are computed assuming a circular beam geometry and the rotating‐vector model. Implications of the results for models of the pulse emission mechanism are briefly discussed.

The kinetic study on the effect of aromatic-connected carbamate (Ar-carbamate) on the curing reaction of phenyl glycidyl ether (PGE) catalyzed by tertiary amine was carried out through thermal analysis of the reaction by differential scanning calorimetry (DSC). By isothermal DSC analysis, the consumption rate of the epoxide group of PGE was found to be a first-order reaction in the presence of aromatic-connected carbamate in the reaction. It was found that the reaction system has a low activation energy (Ea = 4.63 kcal/mol) as compared to the system without Ar-carbamate (Ea = 6.89 kcal/mol). A reaction mechanism was proposed for this reaction system. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:121–127, 1998

It is found that two radiation processes can cause pulsar inner gap breakdown, namely, the curvature radiation (CR) and the inverse Compton scattering (ICS) of high-energy particles off the thermal photons in the neutron star vicinity. The ICS photons are usually more energetic than the CR photons, so that the ICS process is the dominant mechanism to cause pulsar inner gap breakdown. For the ICS process, there are two preferred frequencies for the scattered ?-rays: (1) ?s= 2??B, which is attributed to the resonant scattering, and (2) ?s~ ?2(2.82kT), which is mainly the contribution of the thermal-peak photons, which are usually more energetic. Thus we obtain three modes for pulsar inner gap sparking, namely, the "resonant ICS mode," the "thermal-peak ICS mode," and the "CR mode." A more energetic mode is more likely to dominate the gap-sparking process if the mean free path of the electrons (or positrons) is smaller than the gap height, which is equal to the mean free path of the ?-rays before being absorbed by the magnetic fields. The mean free paths of the electrons (or positrons) for the two ICS modes are functions of the surface temperature of a neutron star, so that we can obtain two "critical temperatures" to distinguish the three modes of pulsar inner gap. If the surface temperatures of the neutron stars fluctuate around the "critical temperatures," the gap properties will change suddenly, which will result in a switching effect in pulsar radiation. The observed "mode changing" phenomenon of some pulsars can be explained by switching between the resonant ICS mode and the thermal-peak ICS mode. The young pulsars near the "birth line" are dominated by the resonant ICS mode, while the pulsars near the "death line" and the millisecond pulsars near the "appearance line" are more likely dominated by the thermal-peak ICS mode.

The process of inverse Compton scattering (ICS) of high-energy particles off the thermal photons above the pulsar polar cap is the dominant mechanism causing polar gap breakdown. In this paper, an approximate analytic description of the parameters of the two modes of the ICS gap, namely, the "resonant ICS gap" and the "thermal ICS gap," are derived under the assumption of a multipolar magnetic field configuration in the neutron star's vicinity. For typical values of P, B, and T, the thermal ICS gap usually has a lower height and smaller potential drop but results in larger Lorentz factors for the secondary particles ejected from the gap.

Black hole masses of AGNs are usually derived from two correlations: one between the black hole mass and the central velocity dispersion and one between the broad line region size and the optical continuum luminosity. Besides applying them in deriving black hole masses of some AGNs, we employed the fundamental plane of elliptical galaxies to estimate the central velocity dispersions of AGN host galaxies and then the black hole masses of AGNs. We also derived another empirical relation between the BLR size and Hβ emission line luminosity and argued that more accurate black hole masses of extremely radio-loud AGNs could be obtained with it than the usual R-L5100 Å relation.

Aims.We study the spectral and polarization properties of supernova remnants (SNRs) using our λ6 cm survey data.

Aims.We attempt to study spatial variations in the spectrum and rotation measures (RMs) of the large-diameter, high-latitude supernova remnant (SNR) CTA 1.

Context.Supernova remnants (SNRs) were often discovered in radio surveys of the Galactic plane. Because of the surface-brightness limit of previous surveys, more faint or confused SNRs await discovery. The Sino-German λ6 cm Galactic plane survey is a sensitive survey with the potential to detect new low-surface-brightness SNRs.

Context.Observations of large supernova remnants (SNRs) at high frequencies are rare, but provide valuable information about their physical properties.

Context.Linear polarization of diffuse Galactic emission is a signature of magnetic fields in the interstellar medium of our Galaxy. Observations at high frequencies are less affected by Faraday depolarization than those at lower frequencies and are able to detect polarized emission from more distant Galactic regions.

Aims.We study polarized short-wavelength emission from the inner Galaxy, which is nearly invisible at long wavelengths because of depolarization. We attempt to obtain information on the diffuse continuum emission at short wavelengths to help us to separate Galactic thermal and non-thermal components.

Context. Linearly polarized Galactic synchrotron emission provides valuable information about the properties of the Galactic magnetic field and the interstellar magneto-ionic medium, when Faraday rotation along the line of sight is properly taken into account.Aims. We aim to survey the Galactic plane at λ6 cm including linear polarization. At such a short wavelength Faraday rotation effects are in general small and the Galactic magnetic field properties can be probed to larger distances than at long wavelengths.Methods. The Urumqi 25-m telescope is used for a sensitive λ6 cm survey in total and polarized intensities. WMAP K-band (22.8 GHz) polarization data are used to restore the absolute zero-level of the Urumqi Uand Qmaps by extrapolation.Results. Total intensity and polarization maps are presented for a Galactic plane region of $129\degr$≤$\ell$≤$230\degr$and |b| ≤$5\degr$in the anti-centre with an angular resolution of $9\farcm5$and an average sensitivity of 0.6 mK and 0.4 mK TBin total and polarized intensity, respectively. We briefly discuss the properties of some extended Faraday Screens detected in the λ6 cm polarization maps.Conclusions. The Sino-German λ6 cm polarization survey provides new information about the properties of the magnetic ISM. The survey also adds valuable information for discrete Galactic objects and is in particular suited to detect extended Faraday Screens with large rotation measures hosting strong regular magnetic fields.

Context. Linearly polarized Galactic synchrotron emission provides valuable information about the properties of the Galactic magnetic field and the interstellar magneto-ionic medium, when Faraday rotation along the line of sight is properly taken into account.Aims. We aim to survey the Galactic plane at λ6 cm including linear polarization. At such a short wavelength Faraday rotation effects are in general small and the Galactic magnetic field properties can be probed to larger distances than at long wavelengths.Methods. The Urumqi 25-m telescope is used for a sensitive λ6 cm survey in total and polarized intensities. WMAP K-band (22.8 GHz) polarization data are used to restore the absolute zero-level of the Urumqi Uand Qmaps by extrapolation.Results. Total intensity and polarization maps are presented for a Galactic plane region of 129° ≤$\ell$≤230° and |b| ≤5° in the anti-centre with an angular resolution of $9\farcm5$and an average sensitivity of 0.6 mK and 0.4 mK TBin total and polarized intensity, respectively. We briefly discuss the properties of some extended Faraday Screens detected in the λ6 cm polarization maps.Conclusions. The Sino-German λ6 cm polarization survey provides new information about the properties of the magnetic ISM. The survey also adds valuable information for discrete Galactic objects and is in particular suited to detect extended Faraday Screens with large rotation measures hosting strong regular magnetic fields.

Context. Linearly polarized Galactic synchrotron emission provides valuable information about the properties of the Galactic magnetic field and the interstellar magneto-ionic medium, when Faraday rotation along the line of sight is properly taken into account.