Search results for "HD"
showing 10 items of 4547 documents
Kotitaide B 03/1902
1902
Kotitaide B 02/1902
1902
Kotitaide B 01/1902
1902
Kotitaide B 06/1902
1902
Kotitaide B 04/1902
1902
Kotitaide B 05/1902
1902
Radio signatures from encounters between neutron stars and QCD-axion minihalos around primordial black holes
2021
Probing the QCD axion dark matter (DM) hypothesis is extremely challenging as the axion interacts very weakly with Standard Model particles. We propose a new avenue to test the QCD axion DM via transient radio signatures coming from encounters between neutron stars (NSs) and axion minihalos around primordial black holes (PBHs). We consider a general QCD axion scenario in which the PQ symmetry breaking occurs before (or during) inflation coexisting with a small fraction of DM in the form of PBHs. The PBHs will unavoidably acquire around them axion minihalos with the typical length scale of parsecs. The axion density in the minihalos may be much higher than the local DM density, and the prese…
Towards cultural transformation : Culture as planetary well-being
2024
Culture covers myriad aspects of human life. Most often it is understood as intellectual or artistic practices, but in a broader view, culture covers the habits, lifestyles, traditions, beliefs, values, and worldviews that shape human lives and societies. Culture also undergoes continuous change and is affected by human actions. Current ecological and well-being crises caused by destructive cultural practices and actions pose an existential risk to both humans and nonhumans. This chapter argues that when challenging, preventing, and changing such destructive human practices and actions, the role of culture is indispensable. Building on and rethinking cultural sustainability, the chapter out…
Solar UV radiation and plant responses : assessing the methodological problems in research concerning stratospheric ozone depletion
2010
Quasi-periodical kinetic instabilities in minimum-B confined plasma
2022
We present the results of an experimental investigation of quasi-periodical kinetic instabilities exhibited by magnetically confined electron cyclotron resonance heated plasmas. The instabilities were detected by measuring plasma microwave emission, electron losses, and wall bremsstrahlung. The instabilities were found to be grouped into fast sequences of periodic plasma losses, separated by ∼100 µs between the bursts, followed by 1–10 ms quiescent periods before the next event. Increasing the plasma energy content by adjusting the plasma heating parameters, in particular the magnetic field strength, makes the instabilities more chaotic in the time domain. Statistical analysis reveals that …