In this work, we have hyperpolarized carbonaceous nanoparticles (D ≈ 10 nm), that is, "nanodiamonds", with 1.1% (13)C (natural abundance) using dynamic nuclear polarization (DNP). The polarization buildup curve showed a signal enhancement with relative intensity up to 4700 at 1.4 K and 100 mW microwave power. (13)C magnetic resonance spectra (MRS) were obtained from the sample at 7 T, and the s...

We consider how vectorial aspects (polarization) of light propagation can be implemented and their origin within a Feynman path integral approach. A key part this scheme is in generalizing the standard optical length from scalar to matrix quantity. Reparametrization invariance along rays allows covariant formulation where take place general curve. gradient index background used demonstrate sche...

Because of the corotation, the polarization angle (PA) curve of a pulsar lags the intensity profile by 4r/Rlc rad in pulse phase. I present a simple and short derivation of this delay-radius relation to show that it is not caused by the aberration (understood as the normal beaming effect) but purely by contribution of corotation to the electron acceleration in the observer’s frame. Available al...

ABSTRACT We explore experimentally possible explanations of the polarization curves sunlight reflected by Barbarian asteroids. Their peculiar are characterized a large-inversion angle, around 30°, which could be related to presence FeO-bearing spinel embedded in Calcium–Aluminum inclusions. In order test this hypothesis, we have measured phase function and degree linear six samples Mg-rich oliv...

We have investigated scattering properties of aggregates, emphasizing the size of constituent monomers comparable with the wavelength of visible light, in order to model the scattering properties of cometary dust. This has differentiated our study from previous investigations of aggregates in which the size of the monomers was much smaller than the wavelength. For aggregates, the absorption cro...

ABSTRACT Optical imaging polarimetry was conducted on the hydrogen poor superluminous supernova 2020znr during three phases after maximum light (≈ +34 d, +288 and +289 d). After instrumental interstellar polarization correction, all measurements are consistent with null-polarization detection. Modelling curve a magnetar spin-down model shows that SN2020znr has similar ejecta parameters to other...

The Crab nebula and its pulsar have been observed for about 3 hours with the high-speed photo-polarimeter OPTIMA in January 2002 at the Calar Alto 3.5 m telescope. The Crab pulsar intensity and polarization are determined at all phases of rotation with higher statistical accuracy than ever. Therefore, we were able to separate the so-called ’off-pulse’ phase emission (with an intensity of about ...

For any projective curve X let M d (X) be the Simpson moduli space of pure dimension one rank 1 degree d sheaves that are semistable with respect to a fixed polarization H on X . When X is a reduced curve the connected component of M d (X) that contains semistable line bundles can be considered as the compactified Jacobian of X . In this paper we give explicitly the structure of this compactifi...