scholarly journals Detecting the gravito-magnetic field of the dark halo of the Milky Way - the LaDaHaD mission concept

2021 ◽  
Author(s):  
Angelo Tartaglia ◽  
Massimo Bassan ◽  
Lorenzo Casalino ◽  
Mariateresa Crosta ◽  
Mario Lattanzi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Angular Momentum ◽  
Milky Way ◽  
Time Of Flight ◽  
Atomic Clocks ◽  
Dark Halo ◽  
The Sun ◽  
Lagrange Points ◽  
The Asymmetry ◽  
Electromagnetic Signals

AbstractWe propose to locate transponders and atomic clocks in at least three of the Lagrange points of the Sun-Earth pair, with the aim of exploiting the time of flight asymmetry between electromagnetic signals travelling in opposite directions along polygonal loops having the Lagrange points at their vertices. The asymmetry is due to the presence of a gravito-magnetic field partly caused by the angular momentum of the Sun, partly originating from the angular momentum of the galactic dark halo in which the Milky Way is embedded. We list also various opportunities which could be associated with the main objective of this Lagrange Dark Halo Detector (LaDaHaD).

scholarly journals Dark angular momentum of the galaxy

2018 ◽  
Vol 27 (14) ◽  
pp. 1847012 ◽  
Author(s):  
Angelo Tartaglia
Keyword(s):  
Magnetic Field ◽  
Dark Matter ◽  
Dark Halo ◽  
The Sun ◽  
Baryonic Matter ◽  
Gravitational Effects ◽  
Lagrange Points ◽  
Visible Matter ◽  
The Galaxy ◽  
The Times

This paper proposes a strategy for detecting the presence of a gravito-magnetic field due to the rotation of the galactic dark halo. Visible matter in galaxies rotates and dark matter, supposed to form a halo incorporating baryonic matter, rotates also, since it interacts gravitationally with the rest. Pursuing the same line of reasoning, dark matter should produce all gravitational effects predicted by general relativity, including a gravito-magnetic field. I discuss a possible strategy for measuring that field. The idea recovers the old Sagnac effect and proposes to use a triangle having three Lagrange points of the Sun–Earth pair at its vertices. The asymmetry in the times of flight along the loop in opposite directions is proportional to the gravito-magnetic galactic field.

scholarly journals The Bulge-disc connection in the Milky Way

2008 ◽  
Vol 4 (S254) ◽  
pp. 145-152
Author(s):  
James Binney
Keyword(s):  
Angular Momentum ◽  
Stellar Population ◽  
Milky Way ◽  
Dark Halo ◽  
Principal Characteristics ◽  
Corotation Radius ◽  
The Galaxy

AbstractBulges come in two flavours – classical and pseudo. The principal characteristics of each flavour are summarised and their impact on discs is considered. Classical bulges probably inhibit the formation of stellar discs. Pseudobulges exchange angular momentum with stars and gas in their companion discs, and also with its embedding dark halo. Since the structure of a pseudobulge depends critically on its angular momentum, these exchanges are expected to modify the bulge. The consequences of this modification are not yet satisfactorily understood. The Galaxy has a pseudobulge. I review the manifestations of its interaction with the disc. More work is needed on the dynamics of gas near the bulge's corotation radius, and on tracing the stellar population in the inner few hundred parsecs of the Galaxy.

scholarly journals Asymmetry in the Earth’s magnetotail neutral sheet rotation due to IMF $$B_y$$ sign?

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Timo Pitkänen ◽  
Anita Kullen ◽  
Lei Cai ◽  
Jong-Sun Park ◽  
Heikki Vanhamäki ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Interplanetary Magnetic Field ◽  
Current Sheet ◽  
The Sun ◽  
Neutral Sheet ◽  
Tail Current ◽  
Cluster Data ◽  
The Asymmetry ◽  
The Cross ◽  
Possible Cause

AbstractEvidence suggests that a non-zero dawn–dusk interplanetary magnetic field (IMF $$B_y$$ B y ) can cause a rotation of the cross-tail current sheet/neutral sheet around its axis aligned with the Sun–Earth line in Earth’s magnetotail. We use Geotail, THEMIS and Cluster data to statistically investigate how the rotation of the neutral sheet depends on the sign and magnitude of IMF $$B_y$$ B y . In our dataset, we find that in the tail range of $$-30<$$ - 30 < XGSM $$<-15$$ < - 15 $$R_{\mathrm{E}}$$ R E , the degree of the neutral sheet rotation is clearly smaller, there appears no significant rotation or even, the rotation is clearly to an unexpected direction for negative IMF $$B_y$$ B y , compared to positive IMF $$B_y$$ B y . Comparison to a model by Tsyganenko et al. (2015, doi:10.5194/angeo-33-1-2015) suggests that this asymmetry in the neutral sheet rotation between positive and negative IMF $$B_y$$ B y conditions is too large to be explained only by the currently known factors. The possible cause of the asymmetry remains unclear.

scholarly journals Relativistic Mass of Gravitational Field

2021 ◽  
Author(s):  
yin zhu
Keyword(s):  
Magnetic Field ◽  
Gravitational Field ◽  
Neutron Star ◽  
Total Mass ◽  
Milky Way ◽  
Fundamental Problem ◽  
Mass Density ◽  
The Sun ◽  
Gravitational Fields ◽  
Relativistic Mass

It is discovered that the gravitational field on the surface of a neutron star is with a relativistic mass density of 2.65*1016~5.87*1018kgm-3 which can be larger than the mass density of the neutron star (~1017kgm-3). And, the total relativistic mass of the gravitational field of the Sun is ~107 times the mass of the Sun. For different stars, the relativistic mass of the gravitational field is larger as the mass density of the star is larger. In the Milky Way, the total relativistic mass of the gravitational fields is much larger than the total mass of the stars, planets and gas. And, the relativistic mass density of the observed strongest magnetic field is 2.17*108kgm-3. This discovery should be a new frame to understand the fundamental problem of physics.

scholarly journals The magnetic field inside the Sun

1988 ◽  
Vol 123 ◽  
pp. 171-174
Author(s):  
W. Dziembowski ◽  
Philip R. Goode
Keyword(s):  
Magnetic Field ◽  
Convection Zone ◽  
Toroidal Magnetic Field ◽  
Solar Dynamo ◽  
The Sun ◽  
Structural Asymmetry ◽  
The Asymmetry ◽  
The Magnetic Field

Duvall, Harvey and Pomerantz (1986) reported the existence of a ‘structural asymmetry’ inside the Sun. We show that this asymmetry is not a consequence of the Sun's rotation. We attribute the asymmetry, rather, to a toroidal magnetic field inside the Sun. Consistency requires a field of about one megagauss located in the lower part of the convection zone. Accounting for such a field would wreak havoc on our understanding of the solar dynamo and convection.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust &amp; Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust &amp; Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

Polar Magnetic Field Reversals of the Sun in Maunder Minimum

2000 ◽  
Vol 179 ◽  
pp. 193-196
Author(s):  
V. I. Makarov ◽  
A. G. Tlatov
Keyword(s):  
Magnetic Field ◽  
Maunder Minimum ◽  
The Sun ◽  
Annual Rings ◽  
Field Reversal ◽  
Polar Magnetic Field ◽  
Pine Trees ◽  
Using Data ◽  
Magnetic Field Reversal

AbstractA possible scenario of polar magnetic field reversal of the Sun during the Maunder Minimum (1645–1715) is discussed using data of magnetic field reversals of the Sun for 1880–1991 and the14Ccontent variations in the bi-annual rings of the pine-trees in 1600–1730 yrs.

PEMANFAATAN RADIASI ENERGI TEGANGAN 150 KV UNTUK LAMPU LED PENERANGAN JALAN

Jurnal Teknik ◽  
2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Mauludi Manfaluthy
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
High Voltage ◽  
Low Frequency ◽  
Energy Utilization ◽  
World Health ◽  
Electromagnetic Signals ◽  
Health Organization ◽  
The Magnetic Field ◽  
Low Frequency Waves

WHO (World Health Organization) concludes that not much effect is caused by electric field up to 20 kV / m in humans. WHO standard also mentions that humans will not be affected by the magnetic field under  100 micro tesla and that the electric field will affect the human body with a maximum standard of 5,000 volts per meter. In this study did not discuss about the effect of high voltage radiation SUTT (High Voltage Air Channel) with human health. The research will focus on energy utilization of SUTT radiation. The combination of electric field and magnetic field on SUTT (70-150KV) can generate electromagnetic (EM) and radiation waves, which are expected to be converted to turn on street lights around the location of high voltage areas or into other forms. The design of this prototype works like an antenna in general that captures electromagnetic signals and converts them into AC waves. With a capacitor that can store the potential energy of AC and Schottky diode waves created specifically for low frequency waves, make the current into one direction (DC). From the research results obtained the current generated from the radiation is very small even though the voltage is big enough.Keywords : Radiance Energy, Joule Thief, and  LED Module.

scholarly journals Energetics of magnetic transients in a solar active region plage

2019 ◽  
Vol 623 ◽  
pp. A176 ◽  
Author(s):  
L. P. Chitta ◽  
A. R. C. Sukarmadji ◽  
L. Rouppe van der Voort ◽  
H. Peter
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Magnetic Flux ◽  
Numerical Simulations ◽  
Extreme Ultraviolet ◽  
Spatial Scales ◽  
Coronal Loops ◽  
The Sun ◽  
Flux Emergence ◽  
Transient Events

Context. Densely packed coronal loops are rooted in photospheric plages in the vicinity of active regions on the Sun. The photospheric magnetic features underlying these plage areas are patches of mostly unidirectional magnetic field extending several arcsec on the solar surface. Aims. We aim to explore the transient nature of the magnetic field, its mixed-polarity characteristics, and the associated energetics in the active region plage using high spatial resolution observations and numerical simulations. Methods. We used photospheric Fe I 6173 Å spectropolarimetric observations of a decaying active region obtained from the Swedish 1-m Solar Telescope (SST). These data were inverted to retrieve the photospheric magnetic field underlying the plage as identified in the extreme-ultraviolet emission maps obtained from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). To obtain better insight into the evolution of extended unidirectional magnetic field patches on the Sun, we performed 3D radiation magnetohydrodynamic simulations of magnetoconvection using the MURaM code. Results. The observations show transient magnetic flux emergence and cancellation events within the extended predominantly unipolar patch on timescales of a few 100 s and on spatial scales comparable to granules. These transient events occur at the footpoints of active region plage loops. In one case the coronal response at the footpoints of these loops is clearly associated with the underlying transient. The numerical simulations also reveal similar magnetic flux emergence and cancellation events that extend to even smaller spatial and temporal scales. Individual simulated transient events transfer an energy flux in excess of 1 MW m−2 through the photosphere. Conclusions. We suggest that the magnetic transients could play an important role in the energetics of active region plage. Both in observations and simulations, the opposite-polarity magnetic field brought up by transient flux emergence cancels with the surrounding plage field. Magnetic reconnection associated with such transient events likely conduits magnetic energy to power the overlying chromosphere and coronal loops.

Sign in / Sign up

Export Citation Format

Share Document