Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with a...Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with an orbital period of less than 1 day.They are fairly rare in the known pulsar population;only five such IMBPs have been discovered before,and one of them is in a globular cluster.Here we report six IMBPs in compact orbits:PSRs J0416+5201,J0520+3722,J1919+1341,J1943+2210,J1947+2304 and J2023+2853,discovered during the Galactic Plane Pulsar Snapshot survey by using the Five-hundred-meter Aperture Spherical radio Telescope,doubling the number of such IMBPs due to the high survey sensitivity in the short survey time of 5 minutes.Follow-up timing observations show that they all have either a CO WD or an ONeMg WD companion with a mass greater than about 0.8M_(⊙)in a very circular orbit with an eccentricity in the order of10^(−5).PSR J0416+5201 should be an ONeMg WD companion with a remarkable minimum mass of 1.28M_(⊙).These massive WD companions lead to a detectable Shapiro delay for PSRs J0416+5201,J0520+3722,J1943+2210,and J2023+2853,indicating that their orbits are highly inclined.From the measurement of the Shapiro delay,the pulsar mass of J1943+2210 was constrained to be 1.84^(+0.11)_(-0.09)M_(⊙),and that of PSR J2023+2853 to be 1.28^(+0.06)_(-0.05)M_(⊙).展开更多
Relaxor ferroelectrics have different properties from that of the normal ferroelectrics,such as dielectric properties with diffuse phase transition and frequency dispersion,specific heat,birefringence,elastic constan...Relaxor ferroelectrics have different properties from that of the normal ferroelectrics,such as dielectric properties with diffuse phase transition and frequency dispersion,specific heat,birefringence,elastic constants and Raman scattering,etc.It is considered that the different properties are related with the polar nanoregions in relaxors.In this work we briefly introduce how we use the high spatial resolution analytical electron microscopy and high resolution electron microscopy methods to investigate the polar nanoregion in Pb(Mg_(1/3)Nb_(2/3))O_(3)(PMN),Pb(Mg_(1/3)Nb_(2/3))O_(3)PbTiO_(3)(PMNPT)and Ba(Ti_(1-x)Sn_(x))O_(3)(BTSn).The main experimental results110 are as mentioned in next three parts.展开更多
基金supported by the National Natural Science Foundation of China(NSFC,Grant Nos.11988101,12133004 and 11833009)the Research Program of the Chinese Academy of Sciences(grant No.QYZDJ-SSW-SLH021 and JZHKYPT-2021-06).
文摘Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with an orbital period of less than 1 day.They are fairly rare in the known pulsar population;only five such IMBPs have been discovered before,and one of them is in a globular cluster.Here we report six IMBPs in compact orbits:PSRs J0416+5201,J0520+3722,J1919+1341,J1943+2210,J1947+2304 and J2023+2853,discovered during the Galactic Plane Pulsar Snapshot survey by using the Five-hundred-meter Aperture Spherical radio Telescope,doubling the number of such IMBPs due to the high survey sensitivity in the short survey time of 5 minutes.Follow-up timing observations show that they all have either a CO WD or an ONeMg WD companion with a mass greater than about 0.8M_(⊙)in a very circular orbit with an eccentricity in the order of10^(−5).PSR J0416+5201 should be an ONeMg WD companion with a remarkable minimum mass of 1.28M_(⊙).These massive WD companions lead to a detectable Shapiro delay for PSRs J0416+5201,J0520+3722,J1943+2210,and J2023+2853,indicating that their orbits are highly inclined.From the measurement of the Shapiro delay,the pulsar mass of J1943+2210 was constrained to be 1.84^(+0.11)_(-0.09)M_(⊙),and that of PSR J2023+2853 to be 1.28^(+0.06)_(-0.05)M_(⊙).
文摘Relaxor ferroelectrics have different properties from that of the normal ferroelectrics,such as dielectric properties with diffuse phase transition and frequency dispersion,specific heat,birefringence,elastic constants and Raman scattering,etc.It is considered that the different properties are related with the polar nanoregions in relaxors.In this work we briefly introduce how we use the high spatial resolution analytical electron microscopy and high resolution electron microscopy methods to investigate the polar nanoregion in Pb(Mg_(1/3)Nb_(2/3))O_(3)(PMN),Pb(Mg_(1/3)Nb_(2/3))O_(3)PbTiO_(3)(PMNPT)and Ba(Ti_(1-x)Sn_(x))O_(3)(BTSn).The main experimental results110 are as mentioned in next three parts.
