direct production at colliders. The charged wino is slightly heavier than the neutral wino by $\simeq 
165~{\rm MeV}$ [@Feng:1999fu]. The small mass difference makes the charged wino live long: $c\tau = \mbox{a few}~{\rm cm}$, which can be detected as a disappearing track at the LHC [@Ibe:2006de; @Asai:2007sw]. The current LHC bound for the wino mass is $m_{\tilde{W}} > 270~{\rm GeV}$ at 95% confidence level [@Aad:2013yna]. At a future lepton collider, direct observation of such a charged track is important. In addition to direct production, processes mediated by wino loops may also provide clues for wino search; see e.g. Ref. [@KEK-talk].

Another promising way of searching for a TeV-scale wino is through cosmic-ray signals from wino dark matter annihilation. The annihilation of winos leads to a variety of cosmic-ray species, e.g. line and continuum photons [@Hisano:2004ds] and antiprotons [@Hisano:2005ec], whose cross section may be enhanced by the Sommerfeld effect. Recent observations of $\gamma$-rays by the H.E.S.S. and Fermi experiments give important constraints, although they are subject to astrophysical uncertainties [@Cohen:2013ama; @Hryczuk:2014hpa]. Cosmic-ray antiprotons can also provide a powerful tool for searching for wino dark matter. While this signal also suffers from astrophysical uncertainties, the on-going AMS-02 experiment can reduce such uncertainties 